src/chrome/browser/about_flags.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "chrome/browser/about_flags.h"
   6
   7 #include <iterator>
   8 #include <map>
   9 #include <set>
  10 #include <utility>
  11
  12 #include "base/command_line.h"
  13 #include "base/memory/singleton.h"
  14 #include "base/metrics/sparse_histogram.h"
  15 #include "base/numerics/safe_conversions.h"
  16 #include "base/stl_util.h"
  17 #include "base/strings/string_number_conversions.h"
  18 #include "base/strings/string_util.h"
  19 #include "base/strings/utf_string_conversions.h"
  20 #include "base/values.h"
  21 #include "cc/base/switches.h"
  22 #include "chrome/browser/bookmarks/enhanced_bookmarks_features.h"
  23 #include "chrome/browser/flags_storage.h"
  24 #include "chrome/common/chrome_content_client.h"
  25 #include "chrome/common/chrome_switches.h"
  26 #include "chrome/grit/generated_resources.h"
  27 #include "components/autofill/core/common/autofill_switches.h"
  28 #include "components/cloud_devices/common/cloud_devices_switches.h"
  29 #include "components/metrics/metrics_hashes.h"
  30 #include "components/nacl/common/nacl_switches.h"
  31 #include "components/search/search_switches.h"
  32 #include "content/public/browser/user_metrics.h"
  33 #include "media/base/media_switches.h"
  34 #include "ui/base/l10n/l10n_util.h"
  35 #include "ui/base/ui_base_switches.h"
  36 #include "ui/display/display_switches.h"
  37 #include "ui/events/event_switches.h"
  38 #include "ui/gfx/switches.h"
  39 #include "ui/gl/gl_switches.h"
  40 #include "ui/keyboard/keyboard_switches.h"
  41 #include "ui/native_theme/native_theme_switches.h"
  42 #include "ui/views/views_switches.h"
  43
  44 #if defined(OS_ANDROID)
  45 #include "chrome/common/chrome_version_info.h"
  46 #include "components/data_reduction_proxy/common/data_reduction_proxy_switches.h"
  47 #include "components/omnibox/omnibox_switches.h"
  48 #else
  49 #include "ui/message_center/message_center_switches.h"
  50 #endif
  51
  52 #if defined(USE_ASH)
  53 #include "ash/ash_switches.h"
  54 #endif
  55
  56 #if defined(OS_CHROMEOS)
  57 #include "chromeos/chromeos_switches.h"
  58 #include "third_party/cros_system_api/switches/chrome_switches.h"
  59 #endif
  60
  61 #if defined(ENABLE_APP_LIST)
  62 #include "ui/app_list/app_list_switches.h"
  63 #endif
  64
  65 #if defined(ENABLE_EXTENSIONS)
  66 #include "extensions/common/switches.h"
  67 #endif
  68
  69 using base::UserMetricsAction;
  70
  71 namespace about_flags {
  72
  73 const base::HistogramBase::Sample kBadSwitchFormatHistogramId = 0;
  74
  75 // Macros to simplify specifying the type.
  76 #define SINGLE_VALUE_TYPE_AND_VALUE(command_line_switch, switch_value) \
  77     Experiment::SINGLE_VALUE, \
  78     command_line_switch, switch_value, NULL, NULL, NULL, 0
  79 #define SINGLE_VALUE_TYPE(command_line_switch) \
  80     SINGLE_VALUE_TYPE_AND_VALUE(command_line_switch, "")
  81 #define ENABLE_DISABLE_VALUE_TYPE_AND_VALUE(enable_switch, enable_value, \
  82                                             disable_switch, disable_value) \
  83     Experiment::ENABLE_DISABLE_VALUE, enable_switch, enable_value, \
  84     disable_switch, disable_value, NULL, 3
  85 #define ENABLE_DISABLE_VALUE_TYPE(enable_switch, disable_switch) \
  86     ENABLE_DISABLE_VALUE_TYPE_AND_VALUE(enable_switch, "", disable_switch, "")
  87 #define MULTI_VALUE_TYPE(choices) \
  88     Experiment::MULTI_VALUE, NULL, NULL, NULL, NULL, choices, arraysize(choices)
  89
  90 namespace {
  91
  92 const unsigned kOsAll = kOsMac | kOsWin | kOsLinux | kOsCrOS | kOsAndroid;
  93 const unsigned kOsDesktop = kOsMac | kOsWin | kOsLinux | kOsCrOS;
  94
  95 // Adds a |StringValue| to |list| for each platform where |bitmask| indicates
  96 // whether the experiment is available on that platform.
  97 void AddOsStrings(unsigned bitmask, base::ListValue* list) {
  98   struct {
  99     unsigned bit;
 100     const char* const name;
 101   } kBitsToOs[] = {
 102     {kOsMac, "Mac"},
 103     {kOsWin, "Windows"},
 104     {kOsLinux, "Linux"},
 105     {kOsCrOS, "Chrome OS"},
 106     {kOsAndroid, "Android"},
 107     {kOsCrOSOwnerOnly, "Chrome OS (owner only)"},
 108   };
 109   for (size_t i = 0; i < ARRAYSIZE_UNSAFE(kBitsToOs); ++i)
 110     if (bitmask & kBitsToOs[i].bit)
 111       list->Append(new base::StringValue(kBitsToOs[i].name));
 112 }
 113
 114 // Convert switch constants to proper CommandLine::StringType strings.
 115 CommandLine::StringType GetSwitchString(const std::string& flag) {
 116   CommandLine cmd_line(CommandLine::NO_PROGRAM);
 117   cmd_line.AppendSwitch(flag);
 118   DCHECK_EQ(2U, cmd_line.argv().size());
 119   return cmd_line.argv()[1];
 120 }
 121
 122 // Scoops flags from a command line.
 123 std::set<CommandLine::StringType> ExtractFlagsFromCommandLine(
 124     const CommandLine& cmdline) {
 125   std::set<CommandLine::StringType> flags;
 126   // First do the ones between --flag-switches-begin and --flag-switches-end.
 127   CommandLine::StringVector::const_iterator first =
 128       std::find(cmdline.argv().begin(), cmdline.argv().end(),
 129                 GetSwitchString(switches::kFlagSwitchesBegin));
 130   CommandLine::StringVector::const_iterator last =
 131       std::find(cmdline.argv().begin(), cmdline.argv().end(),
 132                 GetSwitchString(switches::kFlagSwitchesEnd));
 133   if (first != cmdline.argv().end() && last != cmdline.argv().end())
 134     flags.insert(first + 1, last);
 135 #if defined(OS_CHROMEOS)
 136   // Then add those between --policy-switches-begin and --policy-switches-end.
 137   first = std::find(cmdline.argv().begin(), cmdline.argv().end(),
 138                     GetSwitchString(chromeos::switches::kPolicySwitchesBegin));
 139   last = std::find(cmdline.argv().begin(), cmdline.argv().end(),
 140                    GetSwitchString(chromeos::switches::kPolicySwitchesEnd));
 141   if (first != cmdline.argv().end() && last != cmdline.argv().end())
 142     flags.insert(first + 1, last);
 143 #endif
 144   return flags;
 145 }
 146
 147 const Experiment::Choice kEnableDisplayList2DcanvasChoices[] = {
 148   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 149   { IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED,
 150     switches::kEnableDisplayList2dCanvas, ""},
 151   { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED,
 152     switches::kDisableDisplayList2dCanvas, ""},
 153 };
 154
 155 const Experiment::Choice kEnableCompositingForTransitionChoices[] = {
 156   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 157   { IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED,
 158     switches::kEnableCompositingForTransition, ""},
 159   { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED,
 160     switches::kDisableCompositingForTransition, ""},
 161 };
 162
 163 const Experiment::Choice kTouchEventsChoices[] = {
 164   { IDS_GENERIC_EXPERIMENT_CHOICE_AUTOMATIC, "", "" },
 165   { IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED,
 166     switches::kTouchEvents,
 167     switches::kTouchEventsEnabled },
 168   { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED,
 169     switches::kTouchEvents,
 170     switches::kTouchEventsDisabled }
 171 };
 172
 173 #if defined(USE_AURA)
 174 const Experiment::Choice kOverscrollHistoryNavigationChoices[] = {
 175   { IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED, "", "" },
 176   { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED,
 177     switches::kOverscrollHistoryNavigation,
 178     "0" },
 179   { IDS_OVERSCROLL_HISTORY_NAVIGATION_SIMPLE_UI,
 180     switches::kOverscrollHistoryNavigation,
 181     "2" }
 182 };
 183 #endif
 184
 185 #if !defined(DISABLE_NACL)
 186 const Experiment::Choice kNaClDebugMaskChoices[] = {
 187   // Secure shell can be used on ChromeOS for forwarding the TCP port opened by
 188   // debug stub to a remote machine. Since secure shell uses NaCl, we usually
 189   // want to avoid debugging that. The PNaCl translator is also a NaCl module,
 190   // so by default we want to avoid debugging that.
 191   // NOTE: As the default value must be the empty string, the mask excluding
 192   // the PNaCl translator and secure shell is substituted elsewhere.
 193   { IDS_NACL_DEBUG_MASK_CHOICE_EXCLUDE_UTILS_PNACL, "", "" },
 194   { IDS_NACL_DEBUG_MASK_CHOICE_DEBUG_ALL, switches::kNaClDebugMask, "*://*" },
 195   { IDS_NACL_DEBUG_MASK_CHOICE_INCLUDE_DEBUG,
 196       switches::kNaClDebugMask, "*://*/*debug.nmf" }
 197 };
 198 #endif
 199
 200 const Experiment::Choice kImplSidePaintingChoices[] = {
 201   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 202   { IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED,
 203     switches::kEnableImplSidePainting, ""},
 204   { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED,
 205     switches::kDisableImplSidePainting, ""}
 206 };
 207
 208 const Experiment::Choice kLCDTextChoices[] = {
 209   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 210   { IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED, switches::kEnableLCDText, ""},
 211   { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED, switches::kDisableLCDText, ""}
 212 };
 213
 214 const Experiment::Choice kDistanceFieldTextChoices[] = {
 215   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 216   { IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED,
 217     switches::kEnableDistanceFieldText, "" },
 218   { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED,
 219     switches::kDisableDistanceFieldText, "" }
 220 };
 221
 222 #ifndef USE_AURA
 223 const Experiment::Choice kDelegatedRendererChoices[] = {
 224   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 225   { IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED,
 226     switches::kEnableDelegatedRenderer, ""},
 227   { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED,
 228     switches::kDisableDelegatedRenderer, ""}
 229 };
 230 #endif
 231
 232 const Experiment::Choice kMaxTilesForInterestAreaChoices[] = {
 233   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 234   { IDS_FLAGS_MAX_TILES_FOR_INTEREST_AREA_SHORT,
 235     cc::switches::kMaxTilesForInterestArea, "64"},
 236   { IDS_FLAGS_MAX_TILES_FOR_INTEREST_AREA_TALL,
 237     cc::switches::kMaxTilesForInterestArea, "128"},
 238   { IDS_FLAGS_MAX_TILES_FOR_INTEREST_AREA_GRANDE,
 239     cc::switches::kMaxTilesForInterestArea, "256"},
 240   { IDS_FLAGS_MAX_TILES_FOR_INTEREST_AREA_VENTI,
 241     cc::switches::kMaxTilesForInterestArea, "512"}
 242 };
 243
 244 const Experiment::Choice kDefaultTileWidthChoices[] = {
 245   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 246   { IDS_FLAGS_DEFAULT_TILE_WIDTH_SHORT,
 247     switches::kDefaultTileWidth, "128"},
 248   { IDS_FLAGS_DEFAULT_TILE_WIDTH_TALL,
 249     switches::kDefaultTileWidth, "256"},
 250   { IDS_FLAGS_DEFAULT_TILE_WIDTH_GRANDE,
 251     switches::kDefaultTileWidth, "512"},
 252   { IDS_FLAGS_DEFAULT_TILE_WIDTH_VENTI,
 253     switches::kDefaultTileWidth, "1024"}
 254 };
 255
 256 const Experiment::Choice kDefaultTileHeightChoices[] = {
 257   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 258   { IDS_FLAGS_DEFAULT_TILE_HEIGHT_SHORT,
 259     switches::kDefaultTileHeight, "128"},
 260   { IDS_FLAGS_DEFAULT_TILE_HEIGHT_TALL,
 261     switches::kDefaultTileHeight, "256"},
 262   { IDS_FLAGS_DEFAULT_TILE_HEIGHT_GRANDE,
 263     switches::kDefaultTileHeight, "512"},
 264   { IDS_FLAGS_DEFAULT_TILE_HEIGHT_VENTI,
 265     switches::kDefaultTileHeight, "1024"}
 266 };
 267
 268 const Experiment::Choice kSimpleCacheBackendChoices[] = {
 269   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 270   { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED,
 271     switches::kUseSimpleCacheBackend, "off" },
 272   { IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED,
 273     switches::kUseSimpleCacheBackend, "on"}
 274 };
 275
 276 #if defined(USE_AURA)
 277 const Experiment::Choice kTabCaptureUpscaleQualityChoices[] = {
 278   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 279   { IDS_FLAGS_TAB_CAPTURE_SCALE_QUALITY_FAST,
 280     switches::kTabCaptureUpscaleQuality, "fast" },
 281   { IDS_FLAGS_TAB_CAPTURE_SCALE_QUALITY_GOOD,
 282     switches::kTabCaptureUpscaleQuality, "good" },
 283   { IDS_FLAGS_TAB_CAPTURE_SCALE_QUALITY_BEST,
 284     switches::kTabCaptureUpscaleQuality, "best" },
 285 };
 286
 287 const Experiment::Choice kTabCaptureDownscaleQualityChoices[] = {
 288   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 289   { IDS_FLAGS_TAB_CAPTURE_SCALE_QUALITY_FAST,
 290     switches::kTabCaptureDownscaleQuality, "fast" },
 291   { IDS_FLAGS_TAB_CAPTURE_SCALE_QUALITY_GOOD,
 292     switches::kTabCaptureDownscaleQuality, "good" },
 293   { IDS_FLAGS_TAB_CAPTURE_SCALE_QUALITY_BEST,
 294     switches::kTabCaptureDownscaleQuality, "best" },
 295 };
 296 #endif
 297
 298 #if defined(USE_AURA) || defined(OS_LINUX)
 299 const Experiment::Choice kOverlayScrollbarChoices[] = {
 300   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 301   { IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED,
 302     switches::kEnableOverlayScrollbar, ""},
 303   { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED,
 304     switches::kDisableOverlayScrollbar, ""}
 305 };
 306 #endif
 307
 308 const Experiment::Choice kZeroCopyChoices[] = {
 309   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 310   { IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED,
 311     switches::kEnableZeroCopy, ""},
 312   { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED,
 313     switches::kDisableZeroCopy, ""}
 314 };
 315
 316 #if defined(OS_ANDROID)
 317 const Experiment::Choice kZeroSuggestExperimentsChoices[] = {
 318   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 319   { IDS_FLAGS_ZERO_SUGGEST_MOST_VISITED,
 320     switches::kEnableZeroSuggestMostVisited, ""},
 321   { IDS_FLAGS_ZERO_SUGGEST_ETHER_SERP,
 322     switches::kEnableZeroSuggestEtherSerp, ""},
 323   { IDS_FLAGS_ZERO_SUGGEST_ETHER_NO_SERP,
 324     switches::kEnableZeroSuggestEtherNoSerp, ""},
 325   { IDS_FLAGS_ZERO_SUGGEST_PERSONALIZED,
 326     switches::kEnableZeroSuggestPersonalized, ""},
 327   { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED,
 328     switches::kDisableZeroSuggest, ""}
 329 };
 330 #endif
 331
 332 const Experiment::Choice kNumRasterThreadsChoices[] = {
 333   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 334   { IDS_FLAGS_NUM_RASTER_THREADS_ONE, switches::kNumRasterThreads, "1" },
 335   { IDS_FLAGS_NUM_RASTER_THREADS_TWO, switches::kNumRasterThreads, "2" },
 336   { IDS_FLAGS_NUM_RASTER_THREADS_THREE, switches::kNumRasterThreads, "3" },
 337   { IDS_FLAGS_NUM_RASTER_THREADS_FOUR, switches::kNumRasterThreads, "4" }
 338 };
 339
 340 const Experiment::Choice kEnableGpuRasterizationChoices[] = {
 341   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 342   { IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED,
 343     switches::kEnableGpuRasterization, "" },
 344   { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED,
 345     switches::kDisableGpuRasterization, "" },
 346   { IDS_FLAGS_FORCE_GPU_RASTERIZATION,
 347     switches::kForceGpuRasterization, "" },
 348 };
 349
 350 // We're using independent flags here (as opposed to a common flag with
 351 // different values) to be able to enable/disable the entire experience
 352 // associated with this feature server-side from the FieldTrial (the complete
 353 // experience includes other flag changes as well). It is not currently possible
 354 // to do that with "flag=value" flags.
 355 const Experiment::Choice kSearchButtonInOmniboxChoices[] = {
 356   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 357   { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED,
 358     switches::kDisableSearchButtonInOmnibox, ""},
 359   { IDS_FLAGS_SEARCH_BUTTON_IN_OMNIBOX_ENABLE_FOR_STR,
 360     switches::kEnableSearchButtonInOmniboxForStr, ""},
 361   { IDS_FLAGS_SEARCH_BUTTON_IN_OMNIBOX_ENABLE_FOR_STR_OR_IIP,
 362     switches::kEnableSearchButtonInOmniboxForStrOrIip, ""},
 363   { IDS_FLAGS_SEARCH_BUTTON_IN_OMNIBOX_ENABLED,
 364     switches::kEnableSearchButtonInOmniboxAlways, ""}
 365 };
 366
 367 // See comment above for kSearchButtonInOmniboxChoices. The same reasoning
 368 // applies here.
 369 const Experiment::Choice kOriginChipChoices[] = {
 370   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 371   { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED, switches::kDisableOriginChip, ""},
 372   { IDS_FLAGS_ORIGIN_CHIP_ALWAYS, switches::kEnableOriginChipAlways, ""},
 373   { IDS_FLAGS_ORIGIN_CHIP_ON_SRP, switches::kEnableOriginChipOnSrp, ""}
 374 };
 375
 376 const Experiment::Choice kTouchScrollingModeChoices[] = {
 377   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 378   { IDS_FLAGS_TOUCH_SCROLLING_MODE_TOUCHCANCEL,
 379     switches::kTouchScrollingMode,
 380     switches::kTouchScrollingModeTouchcancel },
 381   { IDS_FLAGS_TOUCH_SCROLLING_MODE_ASYNC_TOUCHMOVE,
 382     switches::kTouchScrollingMode,
 383     switches::kTouchScrollingModeAsyncTouchmove },
 384   { IDS_FLAGS_TOUCH_SCROLLING_MODE_SYNC_TOUCHMOVE,
 385     switches::kTouchScrollingMode,
 386     switches::kTouchScrollingModeSyncTouchmove },
 387 };
 388
 389 #if defined(ENABLE_APP_LIST)
 390 const Experiment::Choice kEnableSyncAppListChoices[] = {
 391   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 392   { IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED,
 393     app_list::switches::kEnableSyncAppList, "" },
 394   { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED,
 395     app_list::switches::kDisableSyncAppList, "" },
 396 };
 397 #endif
 398
 399 const Experiment::Choice kExtensionContentVerificationChoices[] = {
 400   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 401   { IDS_FLAGS_EXTENSION_CONTENT_VERIFICATION_BOOTSTRAP,
 402     switches::kExtensionContentVerification,
 403     switches::kExtensionContentVerificationBootstrap },
 404   { IDS_FLAGS_EXTENSION_CONTENT_VERIFICATION_ENFORCE,
 405     switches::kExtensionContentVerification,
 406     switches::kExtensionContentVerificationEnforce },
 407   { IDS_FLAGS_EXTENSION_CONTENT_VERIFICATION_ENFORCE_STRICT,
 408     switches::kExtensionContentVerification,
 409     switches::kExtensionContentVerificationEnforceStrict },
 410 };
 411
 412 #if defined(OS_ANDROID)
 413 const Experiment::Choice kAnswersInSuggestChoices[] = {
 414   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 415   { IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED,
 416     switches::kEnableAnswersInSuggest, ""},
 417   { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED,
 418     switches::kDisableAnswersInSuggest, ""}
 419 };
 420 #endif
 421
 422 const Experiment::Choice kEnableSettingsWindowChoices[] = {
 423   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 424   { IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED,
 425     ::switches::kEnableSettingsWindow, "" },
 426   { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED,
 427     ::switches::kDisableSettingsWindow, "" },
 428 };
 429
 430 // Note that the value is specified in seconds (where 0 is equivalent to
 431 // disabled).
 432 const Experiment::Choice kRememberCertificateErrorDecisionsChoices[] = {
 433   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 434   { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED,
 435     switches::kRememberCertErrorDecisions,
 436     "-1" },
 437   { IDS_REMEMBER_CERTIFICATE_ERROR_DECISION_CHOICE_ONE_DAY,
 438     switches::kRememberCertErrorDecisions,
 439     "86400" },
 440   { IDS_REMEMBER_CERTIFICATE_ERROR_DECISION_CHOICE_THREE_DAYS,
 441     switches::kRememberCertErrorDecisions,
 442     "259200" },
 443   { IDS_REMEMBER_CERTIFICATE_ERROR_DECISION_CHOICE_ONE_WEEK,
 444     switches::kRememberCertErrorDecisions,
 445     "604800" },
 446   { IDS_REMEMBER_CERTIFICATE_ERROR_DECISION_CHOICE_ONE_MONTH,
 447     switches::kRememberCertErrorDecisions,
 448     "2592000" },
 449   { IDS_REMEMBER_CERTIFICATE_ERROR_DECISION_CHOICE_THREE_MONTHS,
 450     switches::kRememberCertErrorDecisions,
 451     "7776000" },
 452 };
 453
 454 const Experiment::Choice kEnableDropSyncCredentialChoices[] = {
 455   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", ""},
 456   { IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED,
 457     password_manager::switches::kEnableDropSyncCredential, "" },
 458   { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED,
 459     password_manager::switches::kDisableDropSyncCredential, "" },
 460 };
 461
 462 #if defined(OS_MACOSX)
 463 const Experiment::Choice kEnableAVFoundationChoices[] = {
 464   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 465   { IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED, switches::kEnableAVFoundation, ""},
 466   { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED, switches::kForceQTKit, ""}
 467 };
 468 #endif
 469
 470 const Experiment::Choice kAutofillSyncCredentialChoices[] = {
 471   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", ""},
 472   { IDS_ALLOW_AUTOFILL_SYNC_CREDENTIAL,
 473     password_manager::switches::kAllowAutofillSyncCredential, ""},
 474   { IDS_DISALLOW_AUTOFILL_SYNC_CREDENTIAL_FOR_REAUTH,
 475     password_manager::switches::kDisallowAutofillSyncCredentialForReauth, ""},
 476   { IDS_DISALLOW_AUTOFILL_SYNC_CREDENTIAL,
 477     password_manager::switches::kDisallowAutofillSyncCredential, ""},
 478 };
 479
 480 // RECORDING USER METRICS FOR FLAGS:
 481 // -----------------------------------------------------------------------------
 482 // The first line of the experiment is the internal name. If you'd like to
 483 // gather statistics about the usage of your flag, you should append a marker
 484 // comment to the end of the feature name, like so:
 485 //   "my-special-feature",  // FLAGS:RECORD_UMA
 486 //
 487 // After doing that, run
 488 //   tools/metrics/actions/extract_actions.py
 489 // to add the metric to actions.xml (which will enable UMA to record your
 490 // feature flag), then update the <owner>s and <description> sections. Make sure
 491 // to include the actions.xml file when you upload your code for review!
 492 //
 493 // After your feature has shipped under a flag, you can locate the metrics under
 494 // the action name AboutFlags_internal-action-name. Actions are recorded once
 495 // per startup, so you should divide this number by AboutFlags_StartupTick to
 496 // get a sense of usage. Note that this will not be the same as number of users
 497 // with a given feature enabled because users can quit and relaunch the
 498 // application multiple times over a given time interval. The dashboard also
 499 // shows you how many (metrics reporting) users have enabled the flag over the
 500 // last seven days. However, note that this is not the same as the number of
 501 // users who have the flag enabled, since enabling the flag happens once,
 502 // whereas running with the flag enabled happens until the user flips the flag
 503 // again.
 504
 505 // To add a new experiment add to the end of kExperiments. There are two
 506 // distinct types of experiments:
 507 // . SINGLE_VALUE: experiment is either on or off. Use the SINGLE_VALUE_TYPE
 508 //   macro for this type supplying the command line to the macro.
 509 // . MULTI_VALUE: a list of choices, the first of which should correspond to a
 510 //   deactivated state for this lab (i.e. no command line option).  To specify
 511 //   this type of experiment use the macro MULTI_VALUE_TYPE supplying it the
 512 //   array of choices.
 513 // See the documentation of Experiment for details on the fields.
 514 //
 515 // Command-line switches must have entries in enum "LoginCustomFlags" in
 516 // histograms.xml. See note in histograms.xml and don't forget to run
 517 // AboutFlagsHistogramTest unit test to calculate and verify checksum.
 518 //
 519 // When adding a new choice, add it to the end of the list.
 520 const Experiment kExperiments[] = {
 521   {
 522     "ignore-gpu-blacklist",
 523     IDS_FLAGS_IGNORE_GPU_BLACKLIST_NAME,
 524     IDS_FLAGS_IGNORE_GPU_BLACKLIST_DESCRIPTION,
 525     kOsAll,
 526     SINGLE_VALUE_TYPE(switches::kIgnoreGpuBlacklist)
 527   },
 528   {
 529     "disable_layer_squashing",
 530     IDS_FLAGS_DISABLE_LAYER_SQUASHING_NAME,
 531     IDS_FLAGS_DISABLE_LAYER_SQUASHING_DESCRIPTION,
 532     kOsAll,
 533     SINGLE_VALUE_TYPE(switches::kDisableLayerSquashing)
 534   },
 535 #if defined(OS_WIN)
 536   {
 537     "disable-direct-write",
 538     IDS_FLAGS_DISABLE_DIRECT_WRITE_NAME,
 539     IDS_FLAGS_DISABLE_DIRECT_WRITE_DESCRIPTION,
 540     kOsWin,
 541     SINGLE_VALUE_TYPE(switches::kDisableDirectWrite)
 542   },
 543 #endif
 544   {
 545     "enable-experimental-canvas-features",
 546     IDS_FLAGS_ENABLE_EXPERIMENTAL_CANVAS_FEATURES_NAME,
 547     IDS_FLAGS_ENABLE_EXPERIMENTAL_CANVAS_FEATURES_DESCRIPTION,
 548     kOsAll,
 549     SINGLE_VALUE_TYPE(switches::kEnableExperimentalCanvasFeatures)
 550   },
 551   {
 552     "disable-accelerated-2d-canvas",
 553     IDS_FLAGS_DISABLE_ACCELERATED_2D_CANVAS_NAME,
 554     IDS_FLAGS_DISABLE_ACCELERATED_2D_CANVAS_DESCRIPTION,
 555     kOsAll,
 556     SINGLE_VALUE_TYPE(switches::kDisableAccelerated2dCanvas)
 557   },
 558   {
 559     "enable-display-list-2d-canvas",
 560     IDS_FLAGS_ENABLE_DISPLAY_LIST_2D_CANVAS_NAME,
 561     IDS_FLAGS_ENABLE_DISPLAY_LIST_2D_CANVAS_DESCRIPTION,
 562     kOsAll,
 563     MULTI_VALUE_TYPE(kEnableDisplayList2DcanvasChoices)
 564   },
 565   {
 566     "composited-layer-borders",
 567     IDS_FLAGS_COMPOSITED_LAYER_BORDERS,
 568     IDS_FLAGS_COMPOSITED_LAYER_BORDERS_DESCRIPTION,
 569     kOsAll,
 570     SINGLE_VALUE_TYPE(cc::switches::kShowCompositedLayerBorders)
 571   },
 572   {
 573     "show-fps-counter",
 574     IDS_FLAGS_SHOW_FPS_COUNTER,
 575     IDS_FLAGS_SHOW_FPS_COUNTER_DESCRIPTION,
 576     kOsAll,
 577     SINGLE_VALUE_TYPE(cc::switches::kShowFPSCounter)
 578   },
 579   {
 580     "disable-webgl",
 581     IDS_FLAGS_DISABLE_WEBGL_NAME,
 582     IDS_FLAGS_DISABLE_WEBGL_DESCRIPTION,
 583     kOsAll,
 584     SINGLE_VALUE_TYPE(switches::kDisableExperimentalWebGL)
 585   },
 586   {
 587     "disable-webrtc",
 588     IDS_FLAGS_DISABLE_WEBRTC_NAME,
 589     IDS_FLAGS_DISABLE_WEBRTC_DESCRIPTION,
 590     kOsAndroid,
 591 #if defined(OS_ANDROID)
 592     SINGLE_VALUE_TYPE(switches::kDisableWebRTC)
 593 #else
 594     SINGLE_VALUE_TYPE("")
 595 #endif
 596   },
 597 #if defined(ENABLE_WEBRTC)
 598   {
 599     "disable-webrtc-hw-decoding",
 600     IDS_FLAGS_DISABLE_WEBRTC_HW_DECODING_NAME,
 601     IDS_FLAGS_DISABLE_WEBRTC_HW_DECODING_DESCRIPTION,
 602     kOsAndroid | kOsCrOS,
 603     SINGLE_VALUE_TYPE(switches::kDisableWebRtcHWDecoding)
 604   },
 605   {
 606     "disable-webrtc-hw-encoding",
 607     IDS_FLAGS_DISABLE_WEBRTC_HW_ENCODING_NAME,
 608     IDS_FLAGS_DISABLE_WEBRTC_HW_ENCODING_DESCRIPTION,
 609     kOsAndroid | kOsCrOS,
 610     SINGLE_VALUE_TYPE(switches::kDisableWebRtcHWEncoding)
 611   },
 612 #endif
 613 #if defined(OS_ANDROID)
 614   {
 615     "disable-webaudio",
 616     IDS_FLAGS_DISABLE_WEBAUDIO_NAME,
 617     IDS_FLAGS_DISABLE_WEBAUDIO_DESCRIPTION,
 618     kOsAndroid,
 619     SINGLE_VALUE_TYPE(switches::kDisableWebAudio)
 620   },
 621 #endif
 622   {
 623     "enable-compositing-for-transition",
 624     IDS_FLAGS_COMPOSITING_FOR_TRANSITION_NAME,
 625     IDS_FLAGS_COMPOSITING_FOR_TRANSITION_DESCRIPTION,
 626     kOsAll,
 627     MULTI_VALUE_TYPE(kEnableCompositingForTransitionChoices)
 628   },
 629   // Native client is compiled out when DISABLE_NACL is defined.
 630 #if !defined(DISABLE_NACL)
 631   {
 632     "enable-nacl",  // FLAGS:RECORD_UMA
 633     IDS_FLAGS_ENABLE_NACL_NAME,
 634     IDS_FLAGS_ENABLE_NACL_DESCRIPTION,
 635     kOsAll,
 636     SINGLE_VALUE_TYPE(switches::kEnableNaCl)
 637   },
 638   {
 639     "enable-nacl-debug",  // FLAGS:RECORD_UMA
 640     IDS_FLAGS_ENABLE_NACL_DEBUG_NAME,
 641     IDS_FLAGS_ENABLE_NACL_DEBUG_DESCRIPTION,
 642     kOsDesktop,
 643     SINGLE_VALUE_TYPE(switches::kEnableNaClDebug)
 644   },
 645   {
 646     "nacl-debug-mask",  // FLAGS:RECORD_UMA
 647     IDS_FLAGS_NACL_DEBUG_MASK_NAME,
 648     IDS_FLAGS_NACL_DEBUG_MASK_DESCRIPTION,
 649     kOsDesktop,
 650     MULTI_VALUE_TYPE(kNaClDebugMaskChoices)
 651   },
 652 #endif
 653 #if defined(ENABLE_EXTENSIONS)
 654   {
 655     "extension-apis",  // FLAGS:RECORD_UMA
 656     IDS_FLAGS_EXPERIMENTAL_EXTENSION_APIS_NAME,
 657     IDS_FLAGS_EXPERIMENTAL_EXTENSION_APIS_DESCRIPTION,
 658     kOsDesktop,
 659     SINGLE_VALUE_TYPE(extensions::switches::kEnableExperimentalExtensionApis)
 660   },
 661   {
 662     "extensions-on-chrome-urls",
 663     IDS_FLAGS_EXTENSIONS_ON_CHROME_URLS_NAME,
 664     IDS_FLAGS_EXTENSIONS_ON_CHROME_URLS_DESCRIPTION,
 665     kOsAll,
 666     SINGLE_VALUE_TYPE(extensions::switches::kExtensionsOnChromeURLs)
 667   },
 668 #endif
 669   {
 670     "enable-fast-unload",
 671     IDS_FLAGS_ENABLE_FAST_UNLOAD_NAME,
 672     IDS_FLAGS_ENABLE_FAST_UNLOAD_DESCRIPTION,
 673     kOsAll,
 674     SINGLE_VALUE_TYPE(switches::kEnableFastUnload)
 675   },
 676 #if defined(ENABLE_EXTENSIONS)
 677   {
 678     "enable-app-window-controls",
 679     IDS_FLAGS_ENABLE_APP_WINDOW_CONTROLS_NAME,
 680     IDS_FLAGS_ENABLE_APP_WINDOW_CONTROLS_DESCRIPTION,
 681     kOsDesktop,
 682     SINGLE_VALUE_TYPE(extensions::switches::kEnableAppWindowControls)
 683   },
 684 #endif
 685   {
 686     "disable-hyperlink-auditing",
 687     IDS_FLAGS_DISABLE_HYPERLINK_AUDITING_NAME,
 688     IDS_FLAGS_DISABLE_HYPERLINK_AUDITING_DESCRIPTION,
 689     kOsAll,
 690     SINGLE_VALUE_TYPE(switches::kNoPings)
 691   },
 692 #if defined(OS_ANDROID)
 693   {
 694     "contextual-search",
 695     IDS_FLAGS_ENABLE_CONTEXTUAL_SEARCH,
 696     IDS_FLAGS_ENABLE_CONTEXTUAL_SEARCH_DESCRIPTION,
 697     kOsAndroid,
 698     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableContextualSearch,
 699                               switches::kDisableContextualSearch)
 700   },
 701 #endif
 702   {
 703     "show-autofill-type-predictions",
 704     IDS_FLAGS_SHOW_AUTOFILL_TYPE_PREDICTIONS_NAME,
 705     IDS_FLAGS_SHOW_AUTOFILL_TYPE_PREDICTIONS_DESCRIPTION,
 706     kOsAll,
 707     SINGLE_VALUE_TYPE(autofill::switches::kShowAutofillTypePredictions)
 708   },
 709   {
 710     "enable-smooth-scrolling",  // FLAGS:RECORD_UMA
 711     IDS_FLAGS_ENABLE_SMOOTH_SCROLLING_NAME,
 712     IDS_FLAGS_ENABLE_SMOOTH_SCROLLING_DESCRIPTION,
 713     // Can't expose the switch unless the code is compiled in.
 714     // On by default for the Mac (different implementation in WebKit).
 715     kOsLinux,
 716     SINGLE_VALUE_TYPE(switches::kEnableSmoothScrolling)
 717   },
 718 #if defined(USE_AURA) || defined(OS_LINUX)
 719   {
 720     "overlay-scrollbars",
 721     IDS_FLAGS_ENABLE_OVERLAY_SCROLLBARS_NAME,
 722     IDS_FLAGS_ENABLE_OVERLAY_SCROLLBARS_DESCRIPTION,
 723     // Uses the system preference on Mac (a different implementation).
 724     // On Android, this is always enabled.
 725     kOsLinux | kOsCrOS | kOsWin,
 726     MULTI_VALUE_TYPE(kOverlayScrollbarChoices)
 727   },
 728 #endif
 729   {
 730     "enable-panels",
 731     IDS_FLAGS_ENABLE_PANELS_NAME,
 732     IDS_FLAGS_ENABLE_PANELS_DESCRIPTION,
 733     kOsDesktop,
 734     SINGLE_VALUE_TYPE(switches::kEnablePanels)
 735   },
 736   {
 737     // See http://crbug.com/120416 for how to remove this flag.
 738     "save-page-as-mhtml",  // FLAGS:RECORD_UMA
 739     IDS_FLAGS_SAVE_PAGE_AS_MHTML_NAME,
 740     IDS_FLAGS_SAVE_PAGE_AS_MHTML_DESCRIPTION,
 741     kOsMac | kOsWin | kOsLinux,
 742     SINGLE_VALUE_TYPE(switches::kSavePageAsMHTML)
 743   },
 744   {
 745     "enable-quic",
 746     IDS_FLAGS_ENABLE_QUIC_NAME,
 747     IDS_FLAGS_ENABLE_QUIC_DESCRIPTION,
 748     kOsAll,
 749     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableQuic,
 750                               switches::kDisableQuic)
 751   },
 752   {
 753     "enable-spdy4",
 754     IDS_FLAGS_ENABLE_SPDY4_NAME,
 755     IDS_FLAGS_ENABLE_SPDY4_DESCRIPTION,
 756     kOsAll,
 757     SINGLE_VALUE_TYPE(switches::kEnableSpdy4)
 758   },
 759   {
 760     "enable-async-dns",
 761     IDS_FLAGS_ENABLE_ASYNC_DNS_NAME,
 762     IDS_FLAGS_ENABLE_ASYNC_DNS_DESCRIPTION,
 763     kOsWin | kOsMac | kOsLinux | kOsCrOS,
 764     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableAsyncDns,
 765                               switches::kDisableAsyncDns)
 766   },
 767   {
 768     "disable-media-source",
 769     IDS_FLAGS_DISABLE_MEDIA_SOURCE_NAME,
 770     IDS_FLAGS_DISABLE_MEDIA_SOURCE_DESCRIPTION,
 771     kOsAll,
 772     SINGLE_VALUE_TYPE(switches::kDisableMediaSource)
 773   },
 774   {
 775     "enable-encrypted-media",
 776     IDS_FLAGS_ENABLE_ENCRYPTED_MEDIA_NAME,
 777     IDS_FLAGS_ENABLE_ENCRYPTED_MEDIA_DESCRIPTION,
 778     kOsAll,
 779     SINGLE_VALUE_TYPE(switches::kEnableEncryptedMedia)
 780   },
 781   {
 782     "disable-prefixed-encrypted-media",
 783     IDS_FLAGS_DISABLE_PREFIXED_ENCRYPTED_MEDIA_NAME,
 784     IDS_FLAGS_DISABLE_PREFIXED_ENCRYPTED_MEDIA_DESCRIPTION,
 785     kOsAll,
 786     SINGLE_VALUE_TYPE(switches::kDisablePrefixedEncryptedMedia)
 787   },
 788 #if defined(OS_ANDROID)
 789   {
 790     "disable-infobar-for-protected-media-identifier",
 791     IDS_FLAGS_DISABLE_INFOBAR_FOR_PROTECTED_MEDIA_IDENTIFIER_NAME,
 792     IDS_FLAGS_DISABLE_INFOBAR_FOR_PROTECTED_MEDIA_IDENTIFIER_DESCRIPTION,
 793     kOsAndroid,
 794     SINGLE_VALUE_TYPE(switches::kDisableInfobarForProtectedMediaIdentifier)
 795   },
 796   {
 797     "mediadrm-enable-non-compositing",
 798     IDS_FLAGS_MEDIADRM_ENABLE_NON_COMPOSITING_NAME,
 799     IDS_FLAGS_MEDIADRM_ENABLE_NON_COMPOSITING_DESCRIPTION,
 800     kOsAndroid,
 801     SINGLE_VALUE_TYPE(switches::kMediaDrmEnableNonCompositing)
 802   },
 803 #endif  // defined(OS_ANDROID)
 804   {
 805     "enable-javascript-harmony",
 806     IDS_FLAGS_ENABLE_JAVASCRIPT_HARMONY_NAME,
 807     IDS_FLAGS_ENABLE_JAVASCRIPT_HARMONY_DESCRIPTION,
 808     kOsAll,
 809     SINGLE_VALUE_TYPE(switches::kJavaScriptHarmony)
 810   },
 811   {
 812     "disable-software-rasterizer",
 813     IDS_FLAGS_DISABLE_SOFTWARE_RASTERIZER_NAME,
 814     IDS_FLAGS_DISABLE_SOFTWARE_RASTERIZER_DESCRIPTION,
 815 #if defined(ENABLE_SWIFTSHADER)
 816     kOsAll,
 817 #else
 818     0,
 819 #endif
 820     SINGLE_VALUE_TYPE(switches::kDisableSoftwareRasterizer)
 821   },
 822   {
 823     "enable-gpu-rasterization",
 824     IDS_FLAGS_ENABLE_GPU_RASTERIZATION_NAME,
 825     IDS_FLAGS_ENABLE_GPU_RASTERIZATION_DESCRIPTION,
 826     kOsAndroid,
 827     MULTI_VALUE_TYPE(kEnableGpuRasterizationChoices)
 828   },
 829   {
 830     "enable-experimental-web-platform-features",
 831     IDS_FLAGS_EXPERIMENTAL_WEB_PLATFORM_FEATURES_NAME,
 832     IDS_FLAGS_EXPERIMENTAL_WEB_PLATFORM_FEATURES_DESCRIPTION,
 833     kOsAll,
 834     SINGLE_VALUE_TYPE(switches::kEnableExperimentalWebPlatformFeatures)
 835   },
 836   {
 837     "disable-ntp-other-sessions-menu",
 838     IDS_FLAGS_NTP_OTHER_SESSIONS_MENU_NAME,
 839     IDS_FLAGS_NTP_OTHER_SESSIONS_MENU_DESCRIPTION,
 840     kOsDesktop,
 841     SINGLE_VALUE_TYPE(switches::kDisableNTPOtherSessionsMenu)
 842   },
 843   {
 844     "enable-material-design-ntp",
 845     IDS_FLAGS_ENABLE_MATERIAL_DESIGN_NTP_NAME,
 846     IDS_FLAGS_ENABLE_MATERIAL_DESIGN_NTP_DESCRIPTION,
 847     kOsDesktop,
 848     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableMaterialDesignNTP,
 849                               switches::kDisableMaterialDesignNTP)
 850   },
 851   {
 852     "enable-devtools-experiments",
 853     IDS_FLAGS_ENABLE_DEVTOOLS_EXPERIMENTS_NAME,
 854     IDS_FLAGS_ENABLE_DEVTOOLS_EXPERIMENTS_DESCRIPTION,
 855     kOsDesktop,
 856     SINGLE_VALUE_TYPE(switches::kEnableDevToolsExperiments)
 857   },
 858   {
 859     "silent-debugger-extension-api",
 860     IDS_FLAGS_SILENT_DEBUGGER_EXTENSION_API_NAME,
 861     IDS_FLAGS_SILENT_DEBUGGER_EXTENSION_API_DESCRIPTION,
 862     kOsDesktop,
 863     SINGLE_VALUE_TYPE(switches::kSilentDebuggerExtensionAPI)
 864   },
 865   {
 866     "spellcheck-autocorrect",
 867     IDS_FLAGS_SPELLCHECK_AUTOCORRECT,
 868     IDS_FLAGS_SPELLCHECK_AUTOCORRECT_DESCRIPTION,
 869     kOsWin | kOsLinux | kOsCrOS,
 870     SINGLE_VALUE_TYPE(switches::kEnableSpellingAutoCorrect)
 871   },
 872   {
 873     "enable-scroll-prediction",
 874     IDS_FLAGS_ENABLE_SCROLL_PREDICTION_NAME,
 875     IDS_FLAGS_ENABLE_SCROLL_PREDICTION_DESCRIPTION,
 876     kOsDesktop,
 877     SINGLE_VALUE_TYPE(switches::kEnableScrollPrediction)
 878   },
 879   {
 880     "touch-events",
 881     IDS_TOUCH_EVENTS_NAME,
 882     IDS_TOUCH_EVENTS_DESCRIPTION,
 883     kOsDesktop,
 884     MULTI_VALUE_TYPE(kTouchEventsChoices)
 885   },
 886   {
 887     "disable-touch-adjustment",
 888     IDS_DISABLE_TOUCH_ADJUSTMENT_NAME,
 889     IDS_DISABLE_TOUCH_ADJUSTMENT_DESCRIPTION,
 890     kOsWin | kOsLinux | kOsCrOS | kOsAndroid,
 891     SINGLE_VALUE_TYPE(switches::kDisableTouchAdjustment)
 892   },
 893 #if defined(OS_CHROMEOS)
 894   {
 895     "network-portal-notification",
 896     IDS_FLAGS_NETWORK_PORTAL_NOTIFICATION_NAME,
 897     IDS_FLAGS_NETWORK_PORTAL_NOTIFICATION_DESCRIPTION,
 898     kOsCrOS,
 899     ENABLE_DISABLE_VALUE_TYPE(
 900         chromeos::switches::kEnableNetworkPortalNotification,
 901         chromeos::switches::kDisableNetworkPortalNotification)
 902   },
 903 #endif
 904   {
 905     "enable-download-resumption",
 906     IDS_FLAGS_ENABLE_DOWNLOAD_RESUMPTION_NAME,
 907     IDS_FLAGS_ENABLE_DOWNLOAD_RESUMPTION_DESCRIPTION,
 908     kOsDesktop,
 909     SINGLE_VALUE_TYPE(switches::kEnableDownloadResumption)
 910   },
 911 #if defined(ENABLE_PLUGINS)
 912   {
 913     "allow-nacl-socket-api",
 914     IDS_FLAGS_ALLOW_NACL_SOCKET_API_NAME,
 915     IDS_FLAGS_ALLOW_NACL_SOCKET_API_DESCRIPTION,
 916     kOsDesktop,
 917     SINGLE_VALUE_TYPE_AND_VALUE(switches::kAllowNaClSocketAPI, "*")
 918   },
 919 #endif
 920 #if defined(OS_CHROMEOS)
 921   {
 922     "allow-touchpad-three-finger-click",
 923     IDS_FLAGS_ALLOW_TOUCHPAD_THREE_FINGER_CLICK_NAME,
 924     IDS_FLAGS_ALLOW_TOUCHPAD_THREE_FINGER_CLICK_DESCRIPTION,
 925     kOsCrOS,
 926     SINGLE_VALUE_TYPE(chromeos::switches::kEnableTouchpadThreeFingerClick)
 927   },
 928   {
 929     "disable-easy-signin",
 930     IDS_FLAGS_DISABLE_EASY_SIGNIN_NAME,
 931     IDS_FLAGS_DISABLE_EASY_SIGNIN_DESCRIPTION,
 932     kOsCrOSOwnerOnly,
 933     SINGLE_VALUE_TYPE(chromeos::switches::kDisableEasySignin),
 934   },
 935 #endif
 936 #if defined(USE_ASH)
 937   {
 938     "disable-minimize-on-second-launcher-item-click",
 939     IDS_FLAGS_DISABLE_MINIMIZE_ON_SECOND_LAUNCHER_ITEM_CLICK_NAME,
 940     IDS_FLAGS_DISABLE_MINIMIZE_ON_SECOND_LAUNCHER_ITEM_CLICK_DESCRIPTION,
 941     kOsAll,
 942     SINGLE_VALUE_TYPE(switches::kDisableMinimizeOnSecondLauncherItemClick)
 943   },
 944   {
 945     "show-touch-hud",
 946     IDS_FLAGS_SHOW_TOUCH_HUD_NAME,
 947     IDS_FLAGS_SHOW_TOUCH_HUD_DESCRIPTION,
 948     kOsAll,
 949     SINGLE_VALUE_TYPE(ash::switches::kAshTouchHud)
 950   },
 951   {
 952     "enable-pinch",
 953     IDS_FLAGS_ENABLE_PINCH_SCALE_NAME,
 954     IDS_FLAGS_ENABLE_PINCH_SCALE_DESCRIPTION,
 955     kOsLinux | kOsWin | kOsCrOS,
 956     ENABLE_DISABLE_VALUE_TYPE(switches::kEnablePinch, switches::kDisablePinch),
 957   },
 958 #endif  // defined(USE_ASH)
 959   {
 960     "enable-pinch-virtual-viewport",
 961     IDS_FLAGS_ENABLE_PINCH_VIRTUAL_VIEWPORT_NAME,
 962     IDS_FLAGS_ENABLE_PINCH_VIRTUAL_VIEWPORT_DESCRIPTION,
 963     kOsLinux | kOsWin | kOsCrOS | kOsAndroid,
 964     ENABLE_DISABLE_VALUE_TYPE(
 965         cc::switches::kEnablePinchVirtualViewport,
 966         cc::switches::kDisablePinchVirtualViewport),
 967   },
 968   {
 969     "enable-viewport-meta",
 970     IDS_FLAGS_ENABLE_VIEWPORT_META_NAME,
 971     IDS_FLAGS_ENABLE_VIEWPORT_META_DESCRIPTION,
 972     kOsLinux | kOsWin | kOsCrOS | kOsMac,
 973     SINGLE_VALUE_TYPE(switches::kEnableViewportMeta),
 974   },
 975 #if defined(OS_CHROMEOS)
 976   {
 977     "disable-boot-animation",
 978     IDS_FLAGS_DISABLE_BOOT_ANIMATION,
 979     IDS_FLAGS_DISABLE_BOOT_ANIMATION_DESCRIPTION,
 980     kOsCrOSOwnerOnly,
 981     SINGLE_VALUE_TYPE(chromeos::switches::kDisableBootAnimation),
 982   },
 983   {
 984     "enable-video-player-chromecast-support",
 985     IDS_FLAGS_ENABLE_VIDEO_PLAYER_CHROMECAST_SUPPORT_NAME,
 986     IDS_FLAGS_ENABLE_VIDEO_PLAYER_CHROMECAST_SUPPORT_DESCRIPTION,
 987     kOsCrOS,
 988     SINGLE_VALUE_TYPE(chromeos::switches::kEnableVideoPlayerChromecastSupport)
 989   },
 990   {
 991     "disable-office-editing-component-app",
 992     IDS_FLAGS_DISABLE_OFFICE_EDITING_COMPONENT_APP_NAME,
 993     IDS_FLAGS_DISABLE_OFFICE_EDITING_COMPONENT_APP_DESCRIPTION,
 994     kOsCrOS,
 995     SINGLE_VALUE_TYPE(chromeos::switches::kDisableOfficeEditingComponentApp),
 996   },
 997   {
 998     "disable-display-color-calibration",
 999     IDS_FLAGS_DISABLE_DISPLAY_COLOR_CALIBRATION_NAME,
1000     IDS_FLAGS_DISABLE_DISPLAY_COLOR_CALIBRATION_DESCRIPTION,
1001     kOsCrOS,
1002     SINGLE_VALUE_TYPE(ui::switches::kDisableDisplayColorCalibration),
1003   },
1004 #endif  // defined(OS_CHROMEOS)
1005   { "disable-accelerated-video-decode",
1006     IDS_FLAGS_DISABLE_ACCELERATED_VIDEO_DECODE_NAME,
1007     IDS_FLAGS_DISABLE_ACCELERATED_VIDEO_DECODE_DESCRIPTION,
1008     kOsWin | kOsCrOS,
1009     SINGLE_VALUE_TYPE(switches::kDisableAcceleratedVideoDecode),
1010   },
1011 #if defined(USE_ASH)
1012   {
1013     "ash-debug-shortcuts",
1014     IDS_FLAGS_DEBUG_SHORTCUTS_NAME,
1015     IDS_FLAGS_DEBUG_SHORTCUTS_DESCRIPTION,
1016     kOsAll,
1017     SINGLE_VALUE_TYPE(ash::switches::kAshDebugShortcuts),
1018   },
1019   { "ash-enable-touch-view-testing",
1020     IDS_FLAGS_ASH_ENABLE_TOUCH_VIEW_TESTING_NAME,
1021     IDS_FLAGS_ASH_ENABLE_TOUCH_VIEW_TESTING_DESCRIPTION,
1022     kOsCrOS,
1023     SINGLE_VALUE_TYPE(ash::switches::kAshEnableTouchViewTesting),
1024   },
1025   {
1026     "ash-enable-touch-view-touch-feedback",
1027     IDS_FLAGS_ASH_ENABLE_TOUCH_VIEW_TOUCH_FEEDBACK_NAME,
1028     IDS_FLAGS_ASH_ENABLE_TOUCH_VIEW_TOUCH_FEEDBACK_DESCRIPTION,
1029     kOsCrOS,
1030     SINGLE_VALUE_TYPE(ash::switches::kAshEnableTouchViewTouchFeedback),
1031   },
1032   { "ash-disable-text-filtering-in-overview-mode",
1033     IDS_FLAGS_ASH_DISABLE_TEXT_FILTERING_IN_OVERVIEW_MODE_NAME,
1034     IDS_FLAGS_ASH_DISABLE_TEXT_FILTERING_IN_OVERVIEW_MODE_DESCRIPTION,
1035     kOsCrOS,
1036     SINGLE_VALUE_TYPE(ash::switches::kAshDisableTextFilteringInOverviewMode),
1037   },
1038 #endif  // defined(USE_ASH)
1039 #if defined(OS_CHROMEOS)
1040   {
1041     "enable-carrier-switching",
1042     IDS_FLAGS_ENABLE_CARRIER_SWITCHING,
1043     IDS_FLAGS_ENABLE_CARRIER_SWITCHING_DESCRIPTION,
1044     kOsCrOS,
1045     SINGLE_VALUE_TYPE(chromeos::switches::kEnableCarrierSwitching)
1046   },
1047   {
1048     "enable-request-tablet-site",
1049     IDS_FLAGS_ENABLE_REQUEST_TABLET_SITE_NAME,
1050     IDS_FLAGS_ENABLE_REQUEST_TABLET_SITE_DESCRIPTION,
1051     kOsCrOS,
1052     SINGLE_VALUE_TYPE(chromeos::switches::kEnableRequestTabletSite)
1053   },
1054 #endif
1055   {
1056     "debug-packed-apps",
1057     IDS_FLAGS_DEBUG_PACKED_APP_NAME,
1058     IDS_FLAGS_DEBUG_PACKED_APP_DESCRIPTION,
1059     kOsDesktop,
1060     SINGLE_VALUE_TYPE(switches::kDebugPackedApps)
1061   },
1062   {
1063     "enable-password-generation",
1064     IDS_FLAGS_ENABLE_PASSWORD_GENERATION_NAME,
1065     IDS_FLAGS_ENABLE_PASSWORD_GENERATION_DESCRIPTION,
1066     kOsWin | kOsLinux | kOsCrOS | kOsMac,
1067     ENABLE_DISABLE_VALUE_TYPE(autofill::switches::kEnablePasswordGeneration,
1068                               autofill::switches::kDisablePasswordGeneration)
1069   },
1070   {
1071     "enable-automatic-password-saving",
1072     IDS_FLAGS_ENABLE_AUTOMATIC_PASSWORD_SAVING_NAME,
1073     IDS_FLAGS_ENABLE_AUTOMATIC_PASSWORD_SAVING_DESCRIPTION,
1074     kOsDesktop,
1075     SINGLE_VALUE_TYPE(
1076         password_manager::switches::kEnableAutomaticPasswordSaving)
1077   },
1078   {
1079     "password-manager-reauthentication",
1080     IDS_FLAGS_PASSWORD_MANAGER_REAUTHENTICATION_NAME,
1081     IDS_FLAGS_PASSWORD_MANAGER_REAUTHENTICATION_DESCRIPTION,
1082     kOsMac | kOsWin,
1083     SINGLE_VALUE_TYPE(switches::kDisablePasswordManagerReauthentication)
1084   },
1085   {
1086     "enable-android-password-link",
1087     IDS_FLAGS_PASSWORD_MANAGER_ANDROID_LINK_NAME,
1088     IDS_FLAGS_PASSWORD_MANAGER_ANDROID_LINK_DESCRIPTION,
1089     kOsAndroid,
1090     ENABLE_DISABLE_VALUE_TYPE(
1091         password_manager::switches::kEnableAndroidPasswordLink,
1092         password_manager::switches::kDisableAndroidPasswordLink)
1093   },
1094   {
1095     "enable-deferred-image-decoding",
1096     IDS_FLAGS_ENABLE_DEFERRED_IMAGE_DECODING_NAME,
1097     IDS_FLAGS_ENABLE_DEFERRED_IMAGE_DECODING_DESCRIPTION,
1098     kOsMac | kOsLinux | kOsCrOS,
1099     SINGLE_VALUE_TYPE(switches::kEnableDeferredImageDecoding)
1100   },
1101   {
1102     "wallet-service-use-sandbox",
1103     IDS_FLAGS_WALLET_SERVICE_USE_SANDBOX_NAME,
1104     IDS_FLAGS_WALLET_SERVICE_USE_SANDBOX_DESCRIPTION,
1105     kOsAndroid | kOsDesktop,
1106     ENABLE_DISABLE_VALUE_TYPE_AND_VALUE(
1107         autofill::switches::kWalletServiceUseSandbox, "1",
1108         autofill::switches::kWalletServiceUseSandbox, "0")
1109   },
1110 #if defined(USE_AURA)
1111   {
1112     "overscroll-history-navigation",
1113     IDS_FLAGS_OVERSCROLL_HISTORY_NAVIGATION_NAME,
1114     IDS_FLAGS_OVERSCROLL_HISTORY_NAVIGATION_DESCRIPTION,
1115     kOsAll,
1116     MULTI_VALUE_TYPE(kOverscrollHistoryNavigationChoices)
1117   },
1118 #endif
1119   {
1120     "scroll-end-effect",
1121     IDS_FLAGS_SCROLL_END_EFFECT_NAME,
1122     IDS_FLAGS_SCROLL_END_EFFECT_DESCRIPTION,
1123     kOsCrOS,
1124     ENABLE_DISABLE_VALUE_TYPE_AND_VALUE(
1125         switches::kScrollEndEffect, "1",
1126         switches::kScrollEndEffect, "0")
1127   },
1128   {
1129     "enable-renderer-mojo-channel",
1130     IDS_FLAGS_ENABLE_RENDERER_MOJO_CHANNEL_NAME,
1131     IDS_FLAGS_ENABLE_RENDERER_MOJO_CHANNEL_DESCRIPTION,
1132     kOsAll,
1133     SINGLE_VALUE_TYPE(switches::kEnableRendererMojoChannel)
1134   },
1135   {
1136     "enable-touch-drag-drop",
1137     IDS_FLAGS_ENABLE_TOUCH_DRAG_DROP_NAME,
1138     IDS_FLAGS_ENABLE_TOUCH_DRAG_DROP_DESCRIPTION,
1139     kOsWin | kOsCrOS,
1140     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableTouchDragDrop,
1141                               switches::kDisableTouchDragDrop)
1142   },
1143   {
1144     "enable-touch-editing",
1145     IDS_FLAGS_ENABLE_TOUCH_EDITING_NAME,
1146     IDS_FLAGS_ENABLE_TOUCH_EDITING_DESCRIPTION,
1147     kOsCrOS | kOsWin | kOsLinux,
1148     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableTouchEditing,
1149                               switches::kDisableTouchEditing)
1150   },
1151   {
1152     "enable-suggestions-service",
1153     IDS_FLAGS_ENABLE_SUGGESTIONS_SERVICE_NAME,
1154     IDS_FLAGS_ENABLE_SUGGESTIONS_SERVICE_DESCRIPTION,
1155     kOsAndroid | kOsCrOS,
1156     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableSuggestionsService,
1157                               switches::kDisableSuggestionsService)
1158   },
1159   {
1160     "enable-supervised-user-blacklist",
1161     IDS_FLAGS_ENABLE_SUPERVISED_USER_BLACKLIST_NAME,
1162     IDS_FLAGS_ENABLE_SUPERVISED_USER_BLACKLIST_DESCRIPTION,
1163     kOsAndroid | kOsMac | kOsWin | kOsLinux | kOsCrOS,
1164     SINGLE_VALUE_TYPE(switches::kEnableSupervisedUserBlacklist)
1165   },
1166   {
1167     "enable-sync-synced-notifications",
1168     IDS_FLAGS_ENABLE_SYNCED_NOTIFICATIONS_NAME,
1169     IDS_FLAGS_ENABLE_SYNCED_NOTIFICATIONS_DESCRIPTION,
1170     kOsDesktop,
1171     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableSyncSyncedNotifications,
1172                               switches::kDisableSyncSyncedNotifications)
1173   },
1174 #if defined(ENABLE_APP_LIST)
1175   {
1176     "enable-sync-app-list",
1177     IDS_FLAGS_ENABLE_SYNC_APP_LIST_NAME,
1178     IDS_FLAGS_ENABLE_SYNC_APP_LIST_DESCRIPTION,
1179     kOsDesktop,
1180     MULTI_VALUE_TYPE(kEnableSyncAppListChoices)
1181   },
1182 #endif
1183 #if defined(OS_MACOSX)
1184   {
1185     "enable-avfoundation",
1186     IDS_FLAGS_ENABLE_AVFOUNDATION_NAME,
1187     IDS_FLAGS_ENABLE_AVFOUNDATION_DESCRIPTION,
1188     kOsMac,
1189     MULTI_VALUE_TYPE(kEnableAVFoundationChoices)
1190   },
1191 #endif
1192   {
1193     "impl-side-painting",
1194     IDS_FLAGS_IMPL_SIDE_PAINTING_NAME,
1195     IDS_FLAGS_IMPL_SIDE_PAINTING_DESCRIPTION,
1196     kOsAll,
1197     MULTI_VALUE_TYPE(kImplSidePaintingChoices)
1198   },
1199   {
1200     "lcd-text-aa",
1201     IDS_FLAGS_LCD_TEXT_NAME,
1202     IDS_FLAGS_LCD_TEXT_DESCRIPTION,
1203     kOsDesktop,
1204     MULTI_VALUE_TYPE(kLCDTextChoices)
1205   },
1206 #if defined(OS_ANDROID) || defined(OS_MACOSX)
1207   {
1208     "delegated-renderer",
1209     IDS_FLAGS_DELEGATED_RENDERER_NAME,
1210     IDS_FLAGS_DELEGATED_RENDERER_DESCRIPTION,
1211     kOsAndroid,  // TODO(ccameron) Add mac support soon.
1212     MULTI_VALUE_TYPE(kDelegatedRendererChoices)
1213   },
1214 #endif
1215   {
1216     "max-tiles-for-interest-area",
1217     IDS_FLAGS_MAX_TILES_FOR_INTEREST_AREA_NAME,
1218     IDS_FLAGS_MAX_TILES_FOR_INTEREST_AREA_DESCRIPTION,
1219     kOsAll,
1220     MULTI_VALUE_TYPE(kMaxTilesForInterestAreaChoices)
1221   },
1222   {
1223     "enable-offline-auto-reload",
1224     IDS_FLAGS_ENABLE_OFFLINE_AUTO_RELOAD_NAME,
1225     IDS_FLAGS_ENABLE_OFFLINE_AUTO_RELOAD_DESCRIPTION,
1226     kOsAll,
1227     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableOfflineAutoReload,
1228                               switches::kDisableOfflineAutoReload)
1229   },
1230   {
1231     "enable-offline-auto-reload-visible-only",
1232     IDS_FLAGS_ENABLE_OFFLINE_AUTO_RELOAD_VISIBLE_ONLY_NAME,
1233     IDS_FLAGS_ENABLE_OFFLINE_AUTO_RELOAD_VISIBLE_ONLY_DESCRIPTION,
1234     kOsAll,
1235     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableOfflineAutoReloadVisibleOnly,
1236                               switches::kDisableOfflineAutoReloadVisibleOnly)
1237   },
1238   {
1239     "enable-offline-load-stale-cache",
1240     IDS_FLAGS_ENABLE_OFFLINE_LOAD_STALE_NAME,
1241     IDS_FLAGS_ENABLE_OFFLINE_LOAD_STALE_DESCRIPTION,
1242     kOsLinux | kOsMac | kOsWin | kOsAndroid,
1243     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableOfflineLoadStaleCache,
1244                               switches::kDisableOfflineLoadStaleCache)
1245   },
1246   {
1247     "default-tile-width",
1248     IDS_FLAGS_DEFAULT_TILE_WIDTH_NAME,
1249     IDS_FLAGS_DEFAULT_TILE_WIDTH_DESCRIPTION,
1250     kOsAll,
1251     MULTI_VALUE_TYPE(kDefaultTileWidthChoices)
1252   },
1253   {
1254     "default-tile-height",
1255     IDS_FLAGS_DEFAULT_TILE_HEIGHT_NAME,
1256     IDS_FLAGS_DEFAULT_TILE_HEIGHT_DESCRIPTION,
1257     kOsAll,
1258     MULTI_VALUE_TYPE(kDefaultTileHeightChoices)
1259   },
1260 #if defined(OS_ANDROID)
1261   {
1262     "disable-gesture-requirement-for-media-playback",
1263     IDS_FLAGS_DISABLE_GESTURE_REQUIREMENT_FOR_MEDIA_PLAYBACK_NAME,
1264     IDS_FLAGS_DISABLE_GESTURE_REQUIREMENT_FOR_MEDIA_PLAYBACK_DESCRIPTION,
1265     kOsAndroid,
1266     SINGLE_VALUE_TYPE(switches::kDisableGestureRequirementForMediaPlayback)
1267   },
1268 #endif
1269 #if defined(OS_CHROMEOS)
1270   {
1271     "enable-virtual-keyboard",
1272     IDS_FLAGS_ENABLE_VIRTUAL_KEYBOARD_NAME,
1273     IDS_FLAGS_ENABLE_VIRTUAL_KEYBOARD_DESCRIPTION,
1274     kOsCrOS,
1275     SINGLE_VALUE_TYPE(keyboard::switches::kEnableVirtualKeyboard)
1276   },
1277   {
1278     "enable-virtual-keyboard-overscroll",
1279     IDS_FLAGS_ENABLE_VIRTUAL_KEYBOARD_OVERSCROLL_NAME,
1280     IDS_FLAGS_ENABLE_VIRTUAL_KEYBOARD_OVERSCROLL_DESCRIPTION,
1281     kOsCrOS,
1282     ENABLE_DISABLE_VALUE_TYPE(
1283         keyboard::switches::kEnableVirtualKeyboardOverscroll,
1284         keyboard::switches::kDisableVirtualKeyboardOverscroll)
1285   },
1286   {
1287     "enable-swipe-selection",
1288     IDS_FLAGS_ENABLE_SWIPE_SELECTION_NAME,
1289     IDS_FLAGS_ENABLE_SWIPE_SELECTION_DESCRIPTION,
1290     kOsCrOS,
1291     SINGLE_VALUE_TYPE(keyboard::switches::kEnableSwipeSelection)
1292   },
1293   {
1294     "enable-input-view",
1295     IDS_FLAGS_ENABLE_INPUT_VIEW_NAME,
1296     IDS_FLAGS_ENABLE_INPUT_VIEW_DESCRIPTION,
1297     kOsCrOS,
1298     ENABLE_DISABLE_VALUE_TYPE(keyboard::switches::kEnableInputView,
1299                               keyboard::switches::kDisableInputView)
1300   },
1301   {
1302     "enable-experimental-input-view-features",
1303     IDS_FLAGS_ENABLE_EXPERIMENTAL_INPUT_VIEW_FEATURES_NAME,
1304     IDS_FLAGS_ENABLE_EXPERIMENTAL_INPUT_VIEW_FEATURES_DESCRIPTION,
1305     kOsCrOS,
1306     SINGLE_VALUE_TYPE(keyboard::switches::kEnableExperimentalInputViewFeatures)
1307   },
1308 #endif
1309   {
1310     "enable-simple-cache-backend",
1311     IDS_FLAGS_ENABLE_SIMPLE_CACHE_BACKEND_NAME,
1312     IDS_FLAGS_ENABLE_SIMPLE_CACHE_BACKEND_DESCRIPTION,
1313     kOsWin | kOsMac | kOsLinux | kOsCrOS,
1314     MULTI_VALUE_TYPE(kSimpleCacheBackendChoices)
1315   },
1316   {
1317     "enable-tcp-fast-open",
1318     IDS_FLAGS_ENABLE_TCP_FAST_OPEN_NAME,
1319     IDS_FLAGS_ENABLE_TCP_FAST_OPEN_DESCRIPTION,
1320     kOsLinux | kOsCrOS | kOsAndroid,
1321     SINGLE_VALUE_TYPE(switches::kEnableTcpFastOpen)
1322   },
1323 #if defined(ENABLE_SERVICE_DISCOVERY)
1324   {
1325     "device-discovery-notifications",
1326     IDS_FLAGS_DEVICE_DISCOVERY_NOTIFICATIONS_NAME,
1327     IDS_FLAGS_DEVICE_DISCOVERY_NOTIFICATIONS_DESCRIPTION,
1328     kOsDesktop,
1329     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableDeviceDiscoveryNotifications,
1330                               switches::kDisableDeviceDiscoveryNotifications)
1331   },
1332   {
1333     "enable-cloud-devices",
1334     IDS_FLAGS_ENABLE_CLOUD_DEVICES_NAME,
1335     IDS_FLAGS_ENABLE_CLOUD_DEVICES_DESCRIPTION,
1336     kOsDesktop,
1337     SINGLE_VALUE_TYPE(switches::kEnableCloudDevices)
1338   },
1339   {
1340     "enable-print-preview-register-promos",
1341     IDS_FLAGS_ENABLE_PRINT_PREVIEW_REGISTER_PROMOS_NAME,
1342     IDS_FLAGS_ENABLE_PRINT_PREVIEW_REGISTER_PROMOS_DESCRIPTION,
1343     kOsDesktop,
1344     SINGLE_VALUE_TYPE(switches::kEnablePrintPreviewRegisterPromos)
1345   },
1346 #endif  // ENABLE_SERVICE_DISCOVERY
1347 #if defined(OS_WIN)
1348   {
1349     "enable-cloud-print-xps",
1350     IDS_FLAGS_ENABLE_CLOUD_PRINT_XPS_NAME,
1351     IDS_FLAGS_ENABLE_CLOUD_PRINT_XPS_DESCRIPTION,
1352     kOsWin,
1353     SINGLE_VALUE_TYPE(switches::kEnableCloudPrintXps)
1354   },
1355 #endif
1356 #if defined(USE_AURA)
1357   {
1358     "tab-capture-upscale-quality",
1359     IDS_FLAGS_TAB_CAPTURE_UPSCALE_QUALITY_NAME,
1360     IDS_FLAGS_TAB_CAPTURE_UPSCALE_QUALITY_DESCRIPTION,
1361     kOsAll,
1362     MULTI_VALUE_TYPE(kTabCaptureUpscaleQualityChoices)
1363   },
1364   {
1365     "tab-capture-downscale-quality",
1366     IDS_FLAGS_TAB_CAPTURE_DOWNSCALE_QUALITY_NAME,
1367     IDS_FLAGS_TAB_CAPTURE_DOWNSCALE_QUALITY_DESCRIPTION,
1368     kOsAll,
1369     MULTI_VALUE_TYPE(kTabCaptureDownscaleQualityChoices)
1370   },
1371 #endif
1372   {
1373     "enable-spelling-feedback-field-trial",
1374     IDS_FLAGS_ENABLE_SPELLING_FEEDBACK_FIELD_TRIAL_NAME,
1375     IDS_FLAGS_ENABLE_SPELLING_FEEDBACK_FIELD_TRIAL_DESCRIPTION,
1376     kOsAll,
1377     SINGLE_VALUE_TYPE(switches::kEnableSpellingFeedbackFieldTrial)
1378   },
1379   {
1380     "enable-webgl-draft-extensions",
1381     IDS_FLAGS_ENABLE_WEBGL_DRAFT_EXTENSIONS_NAME,
1382     IDS_FLAGS_ENABLE_WEBGL_DRAFT_EXTENSIONS_DESCRIPTION,
1383     kOsAll,
1384     SINGLE_VALUE_TYPE(switches::kEnableWebGLDraftExtensions)
1385   },
1386   {
1387     "enable-web-midi",
1388     IDS_FLAGS_ENABLE_WEB_MIDI_NAME,
1389     IDS_FLAGS_ENABLE_WEB_MIDI_DESCRIPTION,
1390     kOsMac | kOsWin | kOsLinux | kOsCrOS | kOsAndroid,
1391     SINGLE_VALUE_TYPE(switches::kEnableWebMIDI)
1392   },
1393   {
1394     "enable-new-profile-management",
1395     IDS_FLAGS_ENABLE_NEW_PROFILE_MANAGEMENT_NAME,
1396     IDS_FLAGS_ENABLE_NEW_PROFILE_MANAGEMENT_DESCRIPTION,
1397     kOsAndroid | kOsMac | kOsWin | kOsLinux | kOsCrOS,
1398     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableNewProfileManagement,
1399                               switches::kDisableNewProfileManagement)
1400   },
1401   {
1402     "enable-account-consistency",
1403     IDS_FLAGS_ENABLE_ACCOUNT_CONSISTENCY_NAME,
1404     IDS_FLAGS_ENABLE_ACCOUNT_CONSISTENCY_DESCRIPTION,
1405     kOsAndroid | kOsMac | kOsWin | kOsLinux | kOsCrOS,
1406     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableAccountConsistency,
1407                               switches::kDisableAccountConsistency)
1408   },
1409   {
1410     "enable-fast-user-switching",
1411     IDS_FLAGS_ENABLE_FAST_USER_SWITCHING_NAME,
1412     IDS_FLAGS_ENABLE_FAST_USER_SWITCHING_DESCRIPTION,
1413     kOsMac | kOsWin | kOsLinux,
1414     SINGLE_VALUE_TYPE(switches::kFastUserSwitching)
1415   },
1416   {
1417     "enable-new-avatar-menu",
1418     IDS_FLAGS_ENABLE_NEW_AVATAR_MENU_NAME,
1419     IDS_FLAGS_ENABLE_NEW_AVATAR_MENU_DESCRIPTION,
1420     kOsMac | kOsWin | kOsLinux,
1421     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableNewAvatarMenu,
1422                               switches::kDisableNewAvatarMenu)
1423   },
1424   {
1425     "enable-web-based-signin",
1426     IDS_FLAGS_ENABLE_WEB_BASED_SIGNIN_NAME,
1427     IDS_FLAGS_ENABLE_WEB_BASED_SIGNIN_DESCRIPTION,
1428     kOsMac | kOsWin | kOsLinux,
1429     SINGLE_VALUE_TYPE(switches::kEnableWebBasedSignin)
1430   },
1431   {
1432     "enable-google-profile-info",
1433     IDS_FLAGS_ENABLE_GOOGLE_PROFILE_INFO_NAME,
1434     IDS_FLAGS_ENABLE_GOOGLE_PROFILE_INFO_DESCRIPTION,
1435     kOsMac | kOsWin | kOsLinux,
1436     SINGLE_VALUE_TYPE(switches::kGoogleProfileInfo)
1437   },
1438   {
1439     "reset-app-list-install-state",
1440     IDS_FLAGS_RESET_APP_LIST_INSTALL_STATE_NAME,
1441     IDS_FLAGS_RESET_APP_LIST_INSTALL_STATE_DESCRIPTION,
1442     kOsMac | kOsWin | kOsLinux,
1443     SINGLE_VALUE_TYPE(switches::kResetAppListInstallState)
1444   },
1445 #if defined(ENABLE_APP_LIST)
1446 #if defined(OS_LINUX)
1447   {
1448     // This is compiled out on non-Linux platforms because otherwise it would be
1449     // visible on Win/Mac/CrOS but not on Linux GTK, which would be confusing.
1450     // TODO(mgiuca): Remove the #if when Aura is the default on Linux.
1451     "enable-app-list",
1452     IDS_FLAGS_ENABLE_APP_LIST_NAME,
1453     IDS_FLAGS_ENABLE_APP_LIST_DESCRIPTION,
1454     kOsLinux,
1455     SINGLE_VALUE_TYPE(switches::kEnableAppList)
1456   },
1457 #endif
1458 #if defined(ENABLE_EXTENSIONS)
1459   {
1460     "enable-app-view",
1461     IDS_FLAGS_ENABLE_APP_VIEW_NAME,
1462     IDS_FLAGS_ENABLE_APP_VIEW_DESCRIPTION,
1463     kOsDesktop,
1464     SINGLE_VALUE_TYPE(extensions::switches::kEnableAppView)
1465   },
1466 #endif
1467   {
1468     "disable-app-list-app-info",
1469     IDS_FLAGS_DISABLE_APP_INFO_IN_APP_LIST,
1470     IDS_FLAGS_DISABLE_APP_INFO_IN_APP_LIST_DESCRIPTION,
1471     kOsLinux | kOsWin | kOsCrOS,
1472     SINGLE_VALUE_TYPE(app_list::switches::kDisableAppInfo)
1473   },
1474 #endif
1475 #if defined(OS_ANDROID)
1476   {
1477     "enable-accessibility-tab-switcher",
1478     IDS_FLAGS_ENABLE_ACCESSIBILITY_TAB_SWITCHER_NAME,
1479     IDS_FLAGS_ENABLE_ACCESSIBILITY_TAB_SWITCHER_DESCRIPTION,
1480     kOsAndroid,
1481     SINGLE_VALUE_TYPE(switches::kEnableAccessibilityTabSwitcher)
1482   },
1483   {
1484     // TODO(dmazzoni): remove this flag when native android accessibility
1485     // ships in the stable channel. http://crbug.com/356775
1486     "enable-accessibility-script-injection",
1487     IDS_FLAGS_ENABLE_ACCESSIBILITY_SCRIPT_INJECTION_NAME,
1488     IDS_FLAGS_ENABLE_ACCESSIBILITY_SCRIPT_INJECTION_DESCRIPTION,
1489     kOsAndroid,
1490     // Java-only switch: ContentSwitches.ENABLE_ACCESSIBILITY_SCRIPT_INJECTION.
1491     SINGLE_VALUE_TYPE("enable-accessibility-script-injection")
1492   },
1493 #endif
1494   {
1495     "enable-one-copy",
1496     IDS_FLAGS_ONE_COPY_NAME,
1497     IDS_FLAGS_ONE_COPY_DESCRIPTION,
1498     kOsAll,
1499     SINGLE_VALUE_TYPE(switches::kEnableOneCopy)
1500   },
1501   {
1502     "enable-zero-copy",
1503     IDS_FLAGS_ZERO_COPY_NAME,
1504     IDS_FLAGS_ZERO_COPY_DESCRIPTION,
1505     kOsAll,
1506     MULTI_VALUE_TYPE(kZeroCopyChoices)
1507   },
1508 #if defined(OS_CHROMEOS)
1509   {
1510     "enable-first-run-ui-transitions",
1511     IDS_FLAGS_ENABLE_FIRST_RUN_UI_TRANSITIONS_NAME,
1512     IDS_FLAGS_ENABLE_FIRST_RUN_UI_TRANSITIONS_DESCRIPTION,
1513     kOsCrOS,
1514     SINGLE_VALUE_TYPE(chromeos::switches::kEnableFirstRunUITransitions)
1515   },
1516 #endif
1517   {
1518     "enable-streamlined-hosted-apps",
1519     IDS_FLAGS_ENABLE_STREAMLINED_HOSTED_APPS_NAME,
1520     IDS_FLAGS_ENABLE_STREAMLINED_HOSTED_APPS_DESCRIPTION,
1521     kOsWin | kOsCrOS | kOsLinux,
1522     SINGLE_VALUE_TYPE(switches::kEnableStreamlinedHostedApps)
1523   },
1524   {
1525     "enable-ephemeral-apps",
1526     IDS_FLAGS_ENABLE_EPHEMERAL_APPS_NAME,
1527     IDS_FLAGS_ENABLE_EPHEMERAL_APPS_DESCRIPTION,
1528     kOsAll,
1529     SINGLE_VALUE_TYPE(switches::kEnableEphemeralApps)
1530   },
1531   {
1532     "enable-linkable-ephemeral-apps",
1533     IDS_FLAGS_ENABLE_LINKABLE_EPHEMERAL_APPS_NAME,
1534     IDS_FLAGS_ENABLE_LINKABLE_EPHEMERAL_APPS_DESCRIPTION,
1535     kOsAll,
1536     SINGLE_VALUE_TYPE(switches::kEnableLinkableEphemeralApps)
1537   },
1538   {
1539     "enable-service-worker-sync",
1540     IDS_FLAGS_ENABLE_SERVICE_WORKER_SYNC_NAME,
1541     IDS_FLAGS_ENABLE_SERVICE_WORKER_SYNC_DESCRIPTION,
1542     kOsAll,
1543     SINGLE_VALUE_TYPE(switches::kEnableServiceWorkerSync)
1544   },
1545 #if defined(OS_ANDROID)
1546   {
1547     "disable-click-delay",
1548     IDS_FLAGS_DISABLE_CLICK_DELAY_NAME,
1549     IDS_FLAGS_DISABLE_CLICK_DELAY_DESCRIPTION,
1550     kOsAndroid,
1551     // Java-only switch: CommandLine.DISABLE_CLICK_DELAY
1552     SINGLE_VALUE_TYPE("disable-click-delay")
1553   },
1554 #endif
1555 #if defined(OS_MACOSX)
1556   {
1557     "enable-translate-new-ux",
1558     IDS_FLAGS_ENABLE_TRANSLATE_NEW_UX_NAME,
1559     IDS_FLAGS_ENABLE_TRANSLATE_NEW_UX_DESCRIPTION,
1560     kOsMac,
1561     SINGLE_VALUE_TYPE(switches::kEnableTranslateNewUX)
1562   },
1563 #endif
1564 #if defined(TOOLKIT_VIEWS)
1565   {
1566     "disable-views-rect-based-targeting",  // FLAGS:RECORD_UMA
1567     IDS_FLAGS_DISABLE_VIEWS_RECT_BASED_TARGETING_NAME,
1568     IDS_FLAGS_DISABLE_VIEWS_RECT_BASED_TARGETING_DESCRIPTION,
1569     kOsCrOS | kOsWin | kOsLinux,
1570     SINGLE_VALUE_TYPE(views::switches::kDisableViewsRectBasedTargeting)
1571   },
1572   {
1573     "enable-link-disambiguation-popup",
1574     IDS_FLAGS_ENABLE_LINK_DISAMBIGUATION_POPUP_NAME,
1575     IDS_FLAGS_ENABLE_LINK_DISAMBIGUATION_POPUP_DESCRIPTION,
1576     kOsCrOS | kOsWin,
1577     SINGLE_VALUE_TYPE(switches::kEnableLinkDisambiguationPopup)
1578   },
1579 #endif
1580 #if defined(ENABLE_EXTENSIONS)
1581   {
1582     "enable-apps-show-on-first-paint",
1583     IDS_FLAGS_ENABLE_APPS_SHOW_ON_FIRST_PAINT_NAME,
1584     IDS_FLAGS_ENABLE_APPS_SHOW_ON_FIRST_PAINT_DESCRIPTION,
1585     kOsDesktop,
1586     SINGLE_VALUE_TYPE(extensions::switches::kEnableAppsShowOnFirstPaint)
1587   },
1588 #endif
1589   {
1590     "enhanced-bookmarks-experiment",
1591     IDS_FLAGS_ENABLE_ENHANCED_BOOKMARKS_NAME,
1592     IDS_FLAGS_ENABLE_ENHANCED_BOOKMARKS_DESCRIPTION,
1593     kOsDesktop | kOsAndroid,
1594     ENABLE_DISABLE_VALUE_TYPE_AND_VALUE(
1595         switches::kEnhancedBookmarksExperiment, "1",
1596         switches::kEnhancedBookmarksExperiment, "0")
1597   },
1598   {
1599     "manual-enhanced-bookmarks",
1600     IDS_FLAGS_ENABLE_ENHANCED_BOOKMARKS_NAME,
1601     IDS_FLAGS_ENABLE_ENHANCED_BOOKMARKS_DESCRIPTION,
1602     kOsDesktop | kOsAndroid,
1603     SINGLE_VALUE_TYPE(switches::kManualEnhancedBookmarks)
1604   },
1605   {
1606     "manual-enhanced-bookmarks-optout",
1607     IDS_FLAGS_ENABLE_ENHANCED_BOOKMARKS_NAME,
1608     IDS_FLAGS_ENABLE_ENHANCED_BOOKMARKS_DESCRIPTION,
1609     kOsDesktop | kOsAndroid,
1610     SINGLE_VALUE_TYPE(switches::kManualEnhancedBookmarksOptout)
1611   },
1612 #if defined(OS_ANDROID)
1613   {
1614     "enable-zero-suggest-experiment",
1615     IDS_FLAGS_ZERO_SUGGEST_EXPERIMENT_NAME,
1616     IDS_FLAGS_ZERO_SUGGEST_EXPERIMENT_DESCRIPTION,
1617     kOsAndroid,
1618     MULTI_VALUE_TYPE(kZeroSuggestExperimentsChoices)
1619   },
1620   {
1621     "enable-reader-mode-toolbar-icon",
1622     IDS_FLAGS_READER_MODE_EXPERIMENT_NAME,
1623     IDS_FLAGS_READER_MODE_EXPERIMENT_DESCRIPTION,
1624     kOsAndroid,
1625     SINGLE_VALUE_TYPE(switches::kEnableReaderModeToolbarIcon)
1626   },
1627 #endif
1628   {
1629     "num-raster-threads",
1630     IDS_FLAGS_NUM_RASTER_THREADS_NAME,
1631     IDS_FLAGS_NUM_RASTER_THREADS_DESCRIPTION,
1632     kOsAll,
1633     MULTI_VALUE_TYPE(kNumRasterThreadsChoices)
1634   },
1635   {
1636     "origin-chip-in-omnibox",
1637     IDS_FLAGS_ORIGIN_CHIP_NAME,
1638     IDS_FLAGS_ORIGIN_CHIP_DESCRIPTION,
1639     kOsCrOS | kOsMac | kOsWin | kOsLinux,
1640     MULTI_VALUE_TYPE(kOriginChipChoices)
1641   },
1642   {
1643     "search-button-in-omnibox",
1644     IDS_FLAGS_SEARCH_BUTTON_IN_OMNIBOX_NAME,
1645     IDS_FLAGS_SEARCH_BUTTON_IN_OMNIBOX_DESCRIPTION,
1646     kOsCrOS | kOsMac | kOsWin | kOsLinux,
1647     MULTI_VALUE_TYPE(kSearchButtonInOmniboxChoices)
1648   },
1649   {
1650     "disable-ignore-autocomplete-off",
1651     IDS_FLAGS_DISABLE_IGNORE_AUTOCOMPLETE_OFF_NAME,
1652     IDS_FLAGS_DISABLE_IGNORE_AUTOCOMPLETE_OFF_DESCRIPTION,
1653     kOsAll,
1654     SINGLE_VALUE_TYPE(autofill::switches::kDisableIgnoreAutocompleteOff)
1655   },
1656   {
1657     "enable-permissions-bubbles",
1658     IDS_FLAGS_ENABLE_PERMISSIONS_BUBBLES_NAME,
1659     IDS_FLAGS_ENABLE_PERMISSIONS_BUBBLES_DESCRIPTION,
1660     kOsCrOS | kOsMac | kOsWin | kOsLinux,
1661     ENABLE_DISABLE_VALUE_TYPE(switches::kEnablePermissionsBubbles,
1662                               switches::kDisablePermissionsBubbles)
1663   },
1664   {
1665     "enable-session-crashed-bubble",
1666     IDS_FLAGS_ENABLE_SESSION_CRASHED_BUBBLE_NAME,
1667     IDS_FLAGS_ENABLE_SESSION_CRASHED_BUBBLE_DESCRIPTION,
1668     kOsWin | kOsLinux,
1669     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableSessionCrashedBubble,
1670                               switches::kDisableSessionCrashedBubble)
1671   },
1672   {
1673     "out-of-process-pdf",
1674     IDS_FLAGS_OUT_OF_PROCESS_PDF_NAME,
1675     IDS_FLAGS_OUT_OF_PROCESS_PDF_DESCRIPTION,
1676     kOsDesktop,
1677     SINGLE_VALUE_TYPE(switches::kOutOfProcessPdf)
1678   },
1679 #if defined(OS_ANDROID)
1680   {
1681     "disable-cast",
1682     IDS_FLAGS_DISABLE_CAST_NAME,
1683     IDS_FLAGS_DISABLE_CAST_DESCRIPTION,
1684     kOsAndroid,
1685     SINGLE_VALUE_TYPE(switches::kDisableCast)
1686   },
1687   {
1688     "prefetch-search-results",
1689     IDS_FLAGS_PREFETCH_SEARCH_RESULTS_NAME,
1690     IDS_FLAGS_PREFETCH_SEARCH_RESULTS_DESCRIPTION,
1691     kOsAndroid,
1692     SINGLE_VALUE_TYPE(switches::kPrefetchSearchResults)
1693   },
1694 #endif
1695 #if defined(ENABLE_APP_LIST)
1696   {
1697     "enable-experimental-app-list",
1698     IDS_FLAGS_ENABLE_EXPERIMENTAL_APP_LIST_NAME,
1699     IDS_FLAGS_ENABLE_EXPERIMENTAL_APP_LIST_DESCRIPTION,
1700     kOsWin | kOsLinux | kOsCrOS,
1701     SINGLE_VALUE_TYPE(app_list::switches::kEnableExperimentalAppList)
1702   },
1703   {
1704     "enable-centered-app-list",
1705     IDS_FLAGS_ENABLE_CENTERED_APP_LIST_NAME,
1706     IDS_FLAGS_ENABLE_CENTERED_APP_LIST_DESCRIPTION,
1707     kOsWin | kOsLinux | kOsCrOS,
1708     SINGLE_VALUE_TYPE(app_list::switches::kEnableCenteredAppList)
1709   },
1710 #endif
1711   {
1712     "touch-scrolling-mode",
1713     IDS_FLAGS_TOUCH_SCROLLING_MODE_NAME,
1714     IDS_FLAGS_TOUCH_SCROLLING_MODE_DESCRIPTION,
1715     kOsWin | kOsLinux | kOsCrOS | kOsAndroid,
1716     MULTI_VALUE_TYPE(kTouchScrollingModeChoices)
1717   },
1718   {
1719     "disable-threaded-scrolling",
1720     IDS_FLAGS_DISABLE_THREADED_SCROLLING_NAME,
1721     IDS_FLAGS_DISABLE_THREADED_SCROLLING_DESCRIPTION,
1722     kOsWin | kOsLinux | kOsCrOS | kOsAndroid,
1723     SINGLE_VALUE_TYPE(switches::kDisableThreadedScrolling)
1724   },
1725   {
1726     "bleeding-edge-renderer-mode",
1727     IDS_FLAGS_BLEEDING_RENDERER_NAME,
1728     IDS_FLAGS_BLEEDING_RENDERER_DESCRIPTION,
1729     kOsAndroid,
1730     SINGLE_VALUE_TYPE(switches::kEnableBleedingEdgeRenderingFastPaths)
1731   },
1732   {
1733     "enable-settings-window",
1734     IDS_FLAGS_ENABLE_SETTINGS_WINDOW_NAME,
1735     IDS_FLAGS_ENABLE_SETTINGS_WINDOW_DESCRIPTION,
1736     kOsDesktop,
1737     MULTI_VALUE_TYPE(kEnableSettingsWindowChoices)
1738   },
1739 #if defined(OS_ANDROID)
1740   {
1741     "enable-instant-search-clicks",
1742     IDS_FLAGS_ENABLE_INSTANT_SEARCH_CLICKS_NAME,
1743     IDS_FLAGS_ENABLE_INSTANT_SEARCH_CLICKS_DESCRIPTION,
1744     kOsAndroid,
1745     SINGLE_VALUE_TYPE(switches::kEnableInstantSearchClicks)
1746   },
1747 #endif
1748   {
1749     "enable-save-password-bubble",
1750     IDS_FLAGS_ENABLE_SAVE_PASSWORD_BUBBLE_NAME,
1751     IDS_FLAGS_ENABLE_SAVE_PASSWORD_BUBBLE_DESCRIPTION,
1752     kOsWin | kOsLinux | kOsCrOS | kOsMac,
1753     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableSavePasswordBubble,
1754                               switches::kDisableSavePasswordBubble)
1755   },
1756   // TODO(tyoshino): Remove this temporary flag and command line switch. See
1757   // crbug.com/366483 for the target milestone.
1758   {
1759     "allow-insecure-websocket-from-https-origin",
1760     IDS_FLAGS_ALLOW_INSECURE_WEBSOCKET_FROM_HTTPS_ORIGIN_NAME,
1761     IDS_FLAGS_ALLOW_INSECURE_WEBSOCKET_FROM_HTTPS_ORIGIN_DESCRIPTION,
1762     kOsAll,
1763     SINGLE_VALUE_TYPE(switches::kAllowInsecureWebSocketFromHttpsOrigin)
1764   },
1765   {
1766     "enable-apps-file-associations",
1767     IDS_FLAGS_ENABLE_APPS_FILE_ASSOCIATIONS_NAME,
1768     IDS_FLAGS_ENABLE_APPS_FILE_ASSOCIATIONS_DESCRIPTION,
1769     kOsMac,
1770     SINGLE_VALUE_TYPE(switches::kEnableAppsFileAssociations)
1771   },
1772 #if defined(OS_ANDROID)
1773   {
1774     "enable-embeddedsearch-api",
1775     IDS_FLAGS_ENABLE_EMBEDDEDSEARCH_API_NAME,
1776     IDS_FLAGS_ENABLE_EMBEDDEDSEARCH_API_DESCRIPTION,
1777     kOsAndroid,
1778     SINGLE_VALUE_TYPE(switches::kEnableEmbeddedSearchAPI)
1779   },
1780   {
1781     "enable-app-install-alerts",
1782     IDS_FLAGS_ENABLE_APP_INSTALL_ALERTS_NAME,
1783     IDS_FLAGS_ENABLE_APP_INSTALL_ALERTS_DESCRIPTION,
1784     kOsAndroid,
1785     SINGLE_VALUE_TYPE(switches::kEnableAppInstallAlerts)
1786   },
1787 #endif
1788   {
1789     "distance-field-text",
1790     IDS_FLAGS_DISTANCE_FIELD_TEXT_NAME,
1791     IDS_FLAGS_DISTANCE_FIELD_TEXT_DESCRIPTION,
1792     kOsAll,
1793     MULTI_VALUE_TYPE(kDistanceFieldTextChoices)
1794   },
1795   {
1796     "extension-content-verification",
1797     IDS_FLAGS_EXTENSION_CONTENT_VERIFICATION_NAME,
1798     IDS_FLAGS_EXTENSION_CONTENT_VERIFICATION_DESCRIPTION,
1799     kOsDesktop,
1800     MULTI_VALUE_TYPE(kExtensionContentVerificationChoices)
1801   },
1802 #if defined(USE_AURA)
1803   {
1804     "text-input-focus-manager",
1805     IDS_FLAGS_TEXT_INPUT_FOCUS_MANAGER_NAME,
1806     IDS_FLAGS_TEXT_INPUT_FOCUS_MANAGER_DESCRIPTION,
1807     kOsCrOS | kOsLinux | kOsWin,
1808     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableTextInputFocusManager,
1809                               switches::kDisableTextInputFocusManager)
1810   },
1811 #endif
1812 #if defined(ENABLE_EXTENSIONS)
1813   {
1814     "extension-active-script-permission",
1815     IDS_FLAGS_USER_CONSENT_FOR_EXTENSION_SCRIPTS_NAME,
1816     IDS_FLAGS_USER_CONSENT_FOR_EXTENSION_SCRIPTS_DESCRIPTION,
1817     kOsAll,
1818     SINGLE_VALUE_TYPE(extensions::switches::kEnableScriptsRequireAction)
1819   },
1820 #endif
1821   {
1822     "harfbuzz-rendertext",
1823     IDS_FLAGS_HARFBUZZ_RENDERTEXT_NAME,
1824     IDS_FLAGS_HARFBUZZ_RENDERTEXT_DESCRIPTION,
1825     kOsDesktop,
1826     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableHarfBuzzRenderText,
1827                               switches::kDisableHarfBuzzRenderText)
1828   },
1829 #if defined(OS_ANDROID)
1830   {
1831     "answers-in-suggest",
1832     IDS_FLAGS_ENABLE_ANSWERS_IN_SUGGEST_NAME,
1833     IDS_FLAGS_ENABLE_ANSWERS_IN_SUGGEST_DESCRIPTION,
1834     kOsAndroid,
1835     MULTI_VALUE_TYPE(kAnswersInSuggestChoices)
1836   },
1837 #endif
1838 #if defined(OS_ANDROID)
1839   {
1840     "enable-data-reduction-proxy-dev",
1841     IDS_FLAGS_ENABLE_DATA_REDUCTION_PROXY_DEV_NAME,
1842     IDS_FLAGS_ENABLE_DATA_REDUCTION_PROXY_DEV_DESCRIPTION,
1843     kOsAndroid,
1844     ENABLE_DISABLE_VALUE_TYPE(
1845         data_reduction_proxy::switches::kEnableDataReductionProxyDev,
1846         data_reduction_proxy::switches::kDisableDataReductionProxyDev)
1847   },
1848   {
1849     "enable-data-reduction-proxy-alt",
1850     IDS_FLAGS_ENABLE_DATA_REDUCTION_PROXY_ALTERNATIVE_NAME,
1851     IDS_FLAGS_ENABLE_DATA_REDUCTION_PROXY_ALTERNATIVE_DESCRIPTION,
1852     kOsAndroid,
1853     SINGLE_VALUE_TYPE(
1854         data_reduction_proxy::switches::kEnableDataReductionProxyAlt)
1855   },
1856 #endif
1857   {
1858     "enable-experimental-hotwording",
1859     IDS_FLAGS_ENABLE_EXPERIMENTAL_HOTWORDING_NAME,
1860     IDS_FLAGS_ENABLE_EXPERIMENTAL_HOTWORDING_DESCRIPTION,
1861     kOsDesktop,
1862     SINGLE_VALUE_TYPE(switches::kEnableExperimentalHotwording)
1863   },
1864 #if defined(ENABLE_EXTENSIONS)
1865   {
1866     "enable-embedded-extension-options",
1867     IDS_FLAGS_ENABLE_EMBEDDED_EXTENSION_OPTIONS_NAME,
1868     IDS_FLAGS_ENABLE_EMBEDDED_EXTENSION_OPTIONS_DESCRIPTION,
1869     kOsDesktop,
1870     SINGLE_VALUE_TYPE(extensions::switches::kEnableEmbeddedExtensionOptions)
1871   },
1872 #endif
1873   {
1874     "enable-website-settings-manager",
1875     IDS_FLAGS_ENABLE_WEBSITE_SETTINGS_NAME,
1876     IDS_FLAGS_ENABLE_WEBSITE_SETTINGS_DESCRIPTION,
1877     kOsDesktop,
1878     SINGLE_VALUE_TYPE(switches::kEnableWebsiteSettingsManager)
1879   },
1880   {
1881     "remember-cert-error-decisions",
1882     IDS_FLAGS_REMEMBER_CERTIFICATE_ERROR_DECISIONS_NAME,
1883     IDS_FLAGS_REMEMBER_CERTIFICATE_ERROR_DECISIONS_DESCRIPTION,
1884     kOsAll,
1885     MULTI_VALUE_TYPE(kRememberCertificateErrorDecisionsChoices)
1886   },
1887   {
1888     "enable-drop-sync-credential",
1889     IDS_FLAGS_ENABLE_DROP_SYNC_CREDENTIAL_NAME,
1890     IDS_FLAGS_ENABLE_DROP_SYNC_CREDENTIAL_DESCRIPTION,
1891     kOsAll,
1892     MULTI_VALUE_TYPE(kEnableDropSyncCredentialChoices)
1893   },
1894 #if defined(ENABLE_EXTENSIONS)
1895   {
1896     "enable-extension-action-redesign",
1897     IDS_FLAGS_ENABLE_EXTENSION_ACTION_REDESIGN_NAME,
1898     IDS_FLAGS_ENABLE_EXTENSION_ACTION_REDESIGN_DESCRIPTION,
1899     kOsWin | kOsLinux | kOsCrOS,
1900     SINGLE_VALUE_TYPE(extensions::switches::kEnableExtensionActionRedesign)
1901   },
1902 #endif
1903   {
1904     "autofill-sync-credential",
1905     IDS_FLAGS_AUTOFILL_SYNC_CREDENTIAL_NAME,
1906     IDS_FLAGS_AUTOFILL_SYNC_CREDENTIAL_DESCRIPTION,
1907     kOsAll,
1908     MULTI_VALUE_TYPE(kAutofillSyncCredentialChoices)
1909   },
1910 #if !defined(OS_ANDROID)
1911   {
1912     "enable-message-center-always-scroll-up-upon-notification-removal",
1913     IDS_FLAGS_ENABLE_MESSAGE_CENTER_ALWAYS_SCROLL_UP_UPON_REMOVAL_NAME,
1914     IDS_FLAGS_ENABLE_MESSAGE_CENTER_ALWAYS_SCROLL_UP_UPON_REMOVAL_DESCRIPTION,
1915     kOsDesktop,
1916     SINGLE_VALUE_TYPE(
1917         switches::kEnableMessageCenterAlwaysScrollUpUponNotificationRemoval)
1918   },
1919 #endif
1920 #if defined(OS_CHROMEOS)
1921   {
1922     "wake-on-packets",
1923     IDS_FLAGS_WAKE_ON_PACKETS_NAME,
1924     IDS_FLAGS_WAKE_ON_PACKETS_DESCRIPTION,
1925     kOsCrOSOwnerOnly,
1926     SINGLE_VALUE_TYPE(chromeos::switches::kWakeOnPackets)
1927   },
1928 #endif  // OS_CHROMEOS
1929 #if defined(USE_AURA)
1930   {
1931     "enable-tab-audio-muting",
1932     IDS_FLAGS_ENABLE_TAB_AUDIO_MUTING_NAME,
1933     IDS_FLAGS_ENABLE_TAB_AUDIO_MUTING_DESCRIPTION,
1934     kOsWin | kOsLinux | kOsCrOS,
1935     SINGLE_VALUE_TYPE(switches::kEnableTabAudioMuting)
1936   },
1937 #endif  // defined(USE_AURA)
1938
1939   // NOTE: Adding new command-line switches requires adding corresponding
1940   // entries to enum "LoginCustomFlags" in histograms.xml. See note in
1941   // histograms.xml and don't forget to run AboutFlagsHistogramTest unit test.
1942 };
1943
1944 const Experiment* experiments = kExperiments;
1945 size_t num_experiments = arraysize(kExperiments);
1946
1947 // Stores and encapsulates the little state that about:flags has.
1948 class FlagsState {
1949  public:
1950   FlagsState() : needs_restart_(false) {}
1951   void ConvertFlagsToSwitches(FlagsStorage* flags_storage,
1952                               CommandLine* command_line,
1953                               SentinelsMode sentinels);
1954   bool IsRestartNeededToCommitChanges();
1955   void SetExperimentEnabled(
1956       FlagsStorage* flags_storage,
1957       const std::string& internal_name,
1958       bool enable);
1959   void RemoveFlagsSwitches(
1960       std::map<std::string, CommandLine::StringType>* switch_list);
1961   void ResetAllFlags(FlagsStorage* flags_storage);
1962   void reset();
1963
1964   // Returns the singleton instance of this class
1965   static FlagsState* GetInstance() {
1966     return Singleton<FlagsState>::get();
1967   }
1968
1969  private:
1970   bool needs_restart_;
1971   std::map<std::string, std::string> flags_switches_;
1972
1973   DISALLOW_COPY_AND_ASSIGN(FlagsState);
1974 };
1975
1976 // Adds the internal names for the specified experiment to |names|.
1977 void AddInternalName(const Experiment& e, std::set<std::string>* names) {
1978   if (e.type == Experiment::SINGLE_VALUE) {
1979     names->insert(e.internal_name);
1980   } else {
1981     DCHECK(e.type == Experiment::MULTI_VALUE ||
1982            e.type == Experiment::ENABLE_DISABLE_VALUE);
1983     for (int i = 0; i < e.num_choices; ++i)
1984       names->insert(e.NameForChoice(i));
1985   }
1986 }
1987
1988 // Confirms that an experiment is valid, used in a DCHECK in
1989 // SanitizeList below.
1990 bool ValidateExperiment(const Experiment& e) {
1991   switch (e.type) {
1992     case Experiment::SINGLE_VALUE:
1993       DCHECK_EQ(0, e.num_choices);
1994       DCHECK(!e.choices);
1995       break;
1996     case Experiment::MULTI_VALUE:
1997       DCHECK_GT(e.num_choices, 0);
1998       DCHECK(e.choices);
1999       DCHECK(e.choices[0].command_line_switch);
2000       DCHECK_EQ('\0', e.choices[0].command_line_switch[0]);
2001       break;
2002     case Experiment::ENABLE_DISABLE_VALUE:
2003       DCHECK_EQ(3, e.num_choices);
2004       DCHECK(!e.choices);
2005       DCHECK(e.command_line_switch);
2006       DCHECK(e.command_line_value);
2007       DCHECK(e.disable_command_line_switch);
2008       DCHECK(e.disable_command_line_value);
2009       break;
2010     default:
2011       NOTREACHED();
2012   }
2013   return true;
2014 }
2015
2016 // Removes all experiments from prefs::kEnabledLabsExperiments that are
2017 // unknown, to prevent this list to become very long as experiments are added
2018 // and removed.
2019 void SanitizeList(FlagsStorage* flags_storage) {
2020   std::set<std::string> known_experiments;
2021   for (size_t i = 0; i < num_experiments; ++i) {
2022     DCHECK(ValidateExperiment(experiments[i]));
2023     AddInternalName(experiments[i], &known_experiments);
2024   }
2025
2026   std::set<std::string> enabled_experiments = flags_storage->GetFlags();
2027
2028   std::set<std::string> new_enabled_experiments =
2029       base::STLSetIntersection<std::set<std::string> >(
2030           known_experiments, enabled_experiments);
2031
2032   if (new_enabled_experiments != enabled_experiments)
2033     flags_storage->SetFlags(new_enabled_experiments);
2034 }
2035
2036 void GetSanitizedEnabledFlags(
2037     FlagsStorage* flags_storage, std::set<std::string>* result) {
2038   SanitizeList(flags_storage);
2039   *result = flags_storage->GetFlags();
2040 }
2041
2042 bool SkipConditionalExperiment(const Experiment& experiment,
2043                                FlagsStorage* flags_storage) {
2044   if (experiment.internal_name ==
2045       std::string("enhanced-bookmarks-experiment")) {
2046     CommandLine* command_line = CommandLine::ForCurrentProcess();
2047     // Dont't skip experiment if it has non default value.
2048     // It means user selected it.
2049     if (command_line->HasSwitch(switches::kEnhancedBookmarksExperiment))
2050       return false;
2051
2052     return !IsEnhancedBookmarksExperimentEnabled(flags_storage);
2053   }
2054
2055   if ((experiment.internal_name == std::string("manual-enhanced-bookmarks")) ||
2056       (experiment.internal_name ==
2057            std::string("manual-enhanced-bookmarks-optout"))) {
2058     return true;
2059   }
2060
2061 #if defined(OS_ANDROID)
2062   // enable-data-reduction-proxy-dev is only available for the Dev channel.
2063   if (!strcmp("enable-data-reduction-proxy-dev", experiment.internal_name) &&
2064       chrome::VersionInfo::GetChannel() != chrome::VersionInfo::CHANNEL_DEV) {
2065     return true;
2066   }
2067   // enable-data-reduction-proxy-alt is only available for the Dev channel.
2068   if (!strcmp("enable-data-reduction-proxy-alt", experiment.internal_name) &&
2069       chrome::VersionInfo::GetChannel() != chrome::VersionInfo::CHANNEL_DEV) {
2070     return true;
2071   }
2072 #endif
2073
2074   return false;
2075 }
2076
2077
2078 // Variant of GetSanitizedEnabledFlags that also removes any flags that aren't
2079 // enabled on the current platform.
2080 void GetSanitizedEnabledFlagsForCurrentPlatform(
2081     FlagsStorage* flags_storage, std::set<std::string>* result) {
2082   GetSanitizedEnabledFlags(flags_storage, result);
2083
2084   // Filter out any experiments that aren't enabled on the current platform.  We
2085   // don't remove these from prefs else syncing to a platform with a different
2086   // set of experiments would be lossy.
2087   std::set<std::string> platform_experiments;
2088   int current_platform = GetCurrentPlatform();
2089   for (size_t i = 0; i < num_experiments; ++i) {
2090     if (experiments[i].supported_platforms & current_platform)
2091       AddInternalName(experiments[i], &platform_experiments);
2092 #if defined(OS_CHROMEOS)
2093     if (experiments[i].supported_platforms & kOsCrOSOwnerOnly)
2094       AddInternalName(experiments[i], &platform_experiments);
2095 #endif
2096   }
2097
2098   std::set<std::string> new_enabled_experiments =
2099       base::STLSetIntersection<std::set<std::string> >(
2100           platform_experiments, *result);
2101
2102   result->swap(new_enabled_experiments);
2103 }
2104
2105 // Returns the Value representing the choice data in the specified experiment.
2106 base::Value* CreateChoiceData(
2107     const Experiment& experiment,
2108     const std::set<std::string>& enabled_experiments) {
2109   DCHECK(experiment.type == Experiment::MULTI_VALUE ||
2110          experiment.type == Experiment::ENABLE_DISABLE_VALUE);
2111   base::ListValue* result = new base::ListValue;
2112   for (int i = 0; i < experiment.num_choices; ++i) {
2113     base::DictionaryValue* value = new base::DictionaryValue;
2114     const std::string name = experiment.NameForChoice(i);
2115     value->SetString("internal_name", name);
2116     value->SetString("description", experiment.DescriptionForChoice(i));
2117     value->SetBoolean("selected", enabled_experiments.count(name) > 0);
2118     result->Append(value);
2119   }
2120   return result;
2121 }
2122
2123 }  // namespace
2124
2125 std::string Experiment::NameForChoice(int index) const {
2126   DCHECK(type == Experiment::MULTI_VALUE ||
2127          type == Experiment::ENABLE_DISABLE_VALUE);
2128   DCHECK_LT(index, num_choices);
2129   return std::string(internal_name) + testing::kMultiSeparator +
2130          base::IntToString(index);
2131 }
2132
2133 base::string16 Experiment::DescriptionForChoice(int index) const {
2134   DCHECK(type == Experiment::MULTI_VALUE ||
2135          type == Experiment::ENABLE_DISABLE_VALUE);
2136   DCHECK_LT(index, num_choices);
2137   int description_id;
2138   if (type == Experiment::ENABLE_DISABLE_VALUE) {
2139     const int kEnableDisableDescriptionIds[] = {
2140       IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT,
2141       IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED,
2142       IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED,
2143     };
2144     description_id = kEnableDisableDescriptionIds[index];
2145   } else {
2146     description_id = choices[index].description_id;
2147   }
2148   return l10n_util::GetStringUTF16(description_id);
2149 }
2150
2151 void ConvertFlagsToSwitches(FlagsStorage* flags_storage,
2152                             CommandLine* command_line,
2153                             SentinelsMode sentinels) {
2154   FlagsState::GetInstance()->ConvertFlagsToSwitches(flags_storage,
2155                                                     command_line,
2156                                                     sentinels);
2157 }
2158
2159 bool AreSwitchesIdenticalToCurrentCommandLine(
2160     const CommandLine& new_cmdline,
2161     const CommandLine& active_cmdline,
2162     std::set<CommandLine::StringType>* out_difference) {
2163   std::set<CommandLine::StringType> new_flags =
2164       ExtractFlagsFromCommandLine(new_cmdline);
2165   std::set<CommandLine::StringType> active_flags =
2166       ExtractFlagsFromCommandLine(active_cmdline);
2167
2168   bool result = false;
2169   // Needed because std::equal doesn't check if the 2nd set is empty.
2170   if (new_flags.size() == active_flags.size()) {
2171     result =
2172         std::equal(new_flags.begin(), new_flags.end(), active_flags.begin());
2173   }
2174
2175   if (out_difference && !result) {
2176     std::set_symmetric_difference(
2177         new_flags.begin(),
2178         new_flags.end(),
2179         active_flags.begin(),
2180         active_flags.end(),
2181         std::inserter(*out_difference, out_difference->begin()));
2182   }
2183
2184   return result;
2185 }
2186
2187 void GetFlagsExperimentsData(FlagsStorage* flags_storage,
2188                              FlagAccess access,
2189                              base::ListValue* supported_experiments,
2190                              base::ListValue* unsupported_experiments) {
2191   std::set<std::string> enabled_experiments;
2192   GetSanitizedEnabledFlags(flags_storage, &enabled_experiments);
2193
2194   int current_platform = GetCurrentPlatform();
2195
2196   for (size_t i = 0; i < num_experiments; ++i) {
2197     const Experiment& experiment = experiments[i];
2198     if (SkipConditionalExperiment(experiment, flags_storage))
2199       continue;
2200
2201     base::DictionaryValue* data = new base::DictionaryValue();
2202     data->SetString("internal_name", experiment.internal_name);
2203     data->SetString("name",
2204                     l10n_util::GetStringUTF16(experiment.visible_name_id));
2205     data->SetString("description",
2206                     l10n_util::GetStringUTF16(
2207                         experiment.visible_description_id));
2208
2209     base::ListValue* supported_platforms = new base::ListValue();
2210     AddOsStrings(experiment.supported_platforms, supported_platforms);
2211     data->Set("supported_platforms", supported_platforms);
2212
2213     switch (experiment.type) {
2214       case Experiment::SINGLE_VALUE:
2215         data->SetBoolean(
2216             "enabled",
2217             enabled_experiments.count(experiment.internal_name) > 0);
2218         break;
2219       case Experiment::MULTI_VALUE:
2220       case Experiment::ENABLE_DISABLE_VALUE:
2221         data->Set("choices", CreateChoiceData(experiment, enabled_experiments));
2222         break;
2223       default:
2224         NOTREACHED();
2225     }
2226
2227     bool supported = (experiment.supported_platforms & current_platform) != 0;
2228 #if defined(OS_CHROMEOS)
2229     if (access == kOwnerAccessToFlags &&
2230         (experiment.supported_platforms & kOsCrOSOwnerOnly) != 0) {
2231       supported = true;
2232     }
2233 #endif
2234     if (supported)
2235       supported_experiments->Append(data);
2236     else
2237       unsupported_experiments->Append(data);
2238   }
2239 }
2240
2241 bool IsRestartNeededToCommitChanges() {
2242   return FlagsState::GetInstance()->IsRestartNeededToCommitChanges();
2243 }
2244
2245 void SetExperimentEnabled(FlagsStorage* flags_storage,
2246                           const std::string& internal_name,
2247                           bool enable) {
2248   FlagsState::GetInstance()->SetExperimentEnabled(flags_storage,
2249                                                   internal_name, enable);
2250 }
2251
2252 void RemoveFlagsSwitches(
2253     std::map<std::string, CommandLine::StringType>* switch_list) {
2254   FlagsState::GetInstance()->RemoveFlagsSwitches(switch_list);
2255 }
2256
2257 void ResetAllFlags(FlagsStorage* flags_storage) {
2258   FlagsState::GetInstance()->ResetAllFlags(flags_storage);
2259 }
2260
2261 int GetCurrentPlatform() {
2262 #if defined(OS_MACOSX)
2263   return kOsMac;
2264 #elif defined(OS_WIN)
2265   return kOsWin;
2266 #elif defined(OS_CHROMEOS)  // Needs to be before the OS_LINUX check.
2267   return kOsCrOS;
2268 #elif defined(OS_LINUX) || defined(OS_OPENBSD)
2269   return kOsLinux;
2270 #elif defined(OS_ANDROID)
2271   return kOsAndroid;
2272 #else
2273 #error Unknown platform
2274 #endif
2275 }
2276
2277 void RecordUMAStatistics(FlagsStorage* flags_storage) {
2278   std::set<std::string> flags = flags_storage->GetFlags();
2279   for (std::set<std::string>::iterator it = flags.begin(); it != flags.end();
2280        ++it) {
2281     std::string action("AboutFlags_");
2282     action += *it;
2283     content::RecordComputedAction(action);
2284   }
2285   // Since flag metrics are recorded every startup, add a tick so that the
2286   // stats can be made meaningful.
2287   if (flags.size())
2288     content::RecordAction(UserMetricsAction("AboutFlags_StartupTick"));
2289   content::RecordAction(UserMetricsAction("StartupTick"));
2290 }
2291
2292 base::HistogramBase::Sample GetSwitchUMAId(const std::string& switch_name) {
2293   return static_cast<base::HistogramBase::Sample>(
2294       metrics::HashMetricName(switch_name));
2295 }
2296
2297 void ReportCustomFlags(const std::string& uma_histogram_hame,
2298                        const std::set<std::string>& command_line_difference) {
2299   for (std::set<std::string>::const_iterator it =
2300            command_line_difference.begin();
2301        it != command_line_difference.end();
2302        ++it) {
2303     int uma_id = about_flags::kBadSwitchFormatHistogramId;
2304     if (StartsWithASCII(*it, "--", true /* case_sensitive */)) {
2305       // Skip '--' before switch name.
2306       std::string switch_name(it->substr(2));
2307
2308       // Kill value, if any.
2309       const size_t value_pos = switch_name.find('=');
2310       if (value_pos != std::string::npos)
2311         switch_name.resize(value_pos);
2312
2313       uma_id = GetSwitchUMAId(switch_name);
2314     } else {
2315       NOTREACHED() << "ReportCustomFlags(): flag '" << *it
2316                    << "' has incorrect format.";
2317     }
2318     DVLOG(1) << "ReportCustomFlags(): histogram='" << uma_histogram_hame
2319              << "' '" << *it << "', uma_id=" << uma_id;
2320
2321     // Sparse histogram macro does not cache the histogram, so it's safe
2322     // to use macro with non-static histogram name here.
2323     UMA_HISTOGRAM_SPARSE_SLOWLY(uma_histogram_hame, uma_id);
2324   }
2325 }
2326
2327 //////////////////////////////////////////////////////////////////////////////
2328 // FlagsState implementation.
2329
2330 namespace {
2331
2332 typedef std::map<std::string, std::pair<std::string, std::string> >
2333     NameToSwitchAndValueMap;
2334
2335 void SetFlagToSwitchMapping(const std::string& key,
2336                             const std::string& switch_name,
2337                             const std::string& switch_value,
2338                             NameToSwitchAndValueMap* name_to_switch_map) {
2339   DCHECK(name_to_switch_map->end() == name_to_switch_map->find(key));
2340   (*name_to_switch_map)[key] = std::make_pair(switch_name, switch_value);
2341 }
2342
2343 void FlagsState::ConvertFlagsToSwitches(FlagsStorage* flags_storage,
2344                                         CommandLine* command_line,
2345                                         SentinelsMode sentinels) {
2346   if (command_line->HasSwitch(switches::kNoExperiments))
2347     return;
2348
2349   std::set<std::string> enabled_experiments;
2350
2351   GetSanitizedEnabledFlagsForCurrentPlatform(flags_storage,
2352                                              &enabled_experiments);
2353
2354   NameToSwitchAndValueMap name_to_switch_map;
2355   for (size_t i = 0; i < num_experiments; ++i) {
2356     const Experiment& e = experiments[i];
2357     if (e.type == Experiment::SINGLE_VALUE) {
2358       SetFlagToSwitchMapping(e.internal_name, e.command_line_switch,
2359                              e.command_line_value, &name_to_switch_map);
2360     } else if (e.type == Experiment::MULTI_VALUE) {
2361       for (int j = 0; j < e.num_choices; ++j) {
2362         SetFlagToSwitchMapping(e.NameForChoice(j),
2363                                e.choices[j].command_line_switch,
2364                                e.choices[j].command_line_value,
2365                                &name_to_switch_map);
2366       }
2367     } else {
2368       DCHECK_EQ(e.type, Experiment::ENABLE_DISABLE_VALUE);
2369       SetFlagToSwitchMapping(e.NameForChoice(0), std::string(), std::string(),
2370                              &name_to_switch_map);
2371       SetFlagToSwitchMapping(e.NameForChoice(1), e.command_line_switch,
2372                              e.command_line_value, &name_to_switch_map);
2373       SetFlagToSwitchMapping(e.NameForChoice(2), e.disable_command_line_switch,
2374                              e.disable_command_line_value, &name_to_switch_map);
2375     }
2376   }
2377
2378   if (sentinels == kAddSentinels) {
2379     command_line->AppendSwitch(switches::kFlagSwitchesBegin);
2380     flags_switches_.insert(
2381         std::pair<std::string, std::string>(switches::kFlagSwitchesBegin,
2382                                             std::string()));
2383   }
2384   for (std::set<std::string>::iterator it = enabled_experiments.begin();
2385        it != enabled_experiments.end();
2386        ++it) {
2387     const std::string& experiment_name = *it;
2388     NameToSwitchAndValueMap::const_iterator name_to_switch_it =
2389         name_to_switch_map.find(experiment_name);
2390     if (name_to_switch_it == name_to_switch_map.end()) {
2391       NOTREACHED();
2392       continue;
2393     }
2394
2395 #if defined(OS_CHROMEOS)
2396     // On Chrome OS setting command line flag may make browser to restart on
2397     // user login. As this flag eventually will be set to a significant number
2398     // of users skip manual-enhanced-bookmarks to avoid restart.
2399     if (experiment_name == "manual-enhanced-bookmarks")
2400       continue;
2401 #endif
2402
2403     const std::pair<std::string, std::string>&
2404         switch_and_value_pair = name_to_switch_it->second;
2405
2406     CHECK(!switch_and_value_pair.first.empty());
2407     command_line->AppendSwitchASCII(switch_and_value_pair.first,
2408                                     switch_and_value_pair.second);
2409     flags_switches_[switch_and_value_pair.first] = switch_and_value_pair.second;
2410   }
2411   if (sentinels == kAddSentinels) {
2412     command_line->AppendSwitch(switches::kFlagSwitchesEnd);
2413     flags_switches_.insert(
2414         std::pair<std::string, std::string>(switches::kFlagSwitchesEnd,
2415                                             std::string()));
2416   }
2417 }
2418
2419 bool FlagsState::IsRestartNeededToCommitChanges() {
2420   return needs_restart_;
2421 }
2422
2423 void FlagsState::SetExperimentEnabled(FlagsStorage* flags_storage,
2424                                       const std::string& internal_name,
2425                                       bool enable) {
2426   size_t at_index = internal_name.find(testing::kMultiSeparator);
2427   if (at_index != std::string::npos) {
2428     DCHECK(enable);
2429     // We're being asked to enable a multi-choice experiment. Disable the
2430     // currently selected choice.
2431     DCHECK_NE(at_index, 0u);
2432     const std::string experiment_name = internal_name.substr(0, at_index);
2433     SetExperimentEnabled(flags_storage, experiment_name, false);
2434
2435     // And enable the new choice, if it is not the default first choice.
2436     if (internal_name != experiment_name + "@0") {
2437       std::set<std::string> enabled_experiments;
2438       GetSanitizedEnabledFlags(flags_storage, &enabled_experiments);
2439       needs_restart_ |= enabled_experiments.insert(internal_name).second;
2440       flags_storage->SetFlags(enabled_experiments);
2441     }
2442     return;
2443   }
2444
2445   std::set<std::string> enabled_experiments;
2446   GetSanitizedEnabledFlags(flags_storage, &enabled_experiments);
2447
2448   const Experiment* e = NULL;
2449   for (size_t i = 0; i < num_experiments; ++i) {
2450     if (experiments[i].internal_name == internal_name) {
2451       e = experiments + i;
2452       break;
2453     }
2454   }
2455   DCHECK(e);
2456
2457   if (e->type == Experiment::SINGLE_VALUE) {
2458     if (enable)
2459       needs_restart_ |= enabled_experiments.insert(internal_name).second;
2460     else
2461       needs_restart_ |= (enabled_experiments.erase(internal_name) > 0);
2462   } else {
2463     if (enable) {
2464       // Enable the first choice.
2465       needs_restart_ |= enabled_experiments.insert(e->NameForChoice(0)).second;
2466     } else {
2467       // Find the currently enabled choice and disable it.
2468       for (int i = 0; i < e->num_choices; ++i) {
2469         std::string choice_name = e->NameForChoice(i);
2470         if (enabled_experiments.find(choice_name) !=
2471             enabled_experiments.end()) {
2472           needs_restart_ = true;
2473           enabled_experiments.erase(choice_name);
2474           // Continue on just in case there's a bug and more than one
2475           // experiment for this choice was enabled.
2476         }
2477       }
2478     }
2479   }
2480
2481   flags_storage->SetFlags(enabled_experiments);
2482 }
2483
2484 void FlagsState::RemoveFlagsSwitches(
2485     std::map<std::string, CommandLine::StringType>* switch_list) {
2486   for (std::map<std::string, std::string>::const_iterator
2487            it = flags_switches_.begin(); it != flags_switches_.end(); ++it) {
2488     switch_list->erase(it->first);
2489   }
2490 }
2491
2492 void FlagsState::ResetAllFlags(FlagsStorage* flags_storage) {
2493   needs_restart_ = true;
2494
2495   std::set<std::string> no_experiments;
2496   flags_storage->SetFlags(no_experiments);
2497 }
2498
2499 void FlagsState::reset() {
2500   needs_restart_ = false;
2501   flags_switches_.clear();
2502 }
2503
2504 }  // namespace
2505
2506 namespace testing {
2507
2508 // WARNING: '@' is also used in the html file. If you update this constant you
2509 // also need to update the html file.
2510 const char kMultiSeparator[] = "@";
2511
2512 void ClearState() {
2513   FlagsState::GetInstance()->reset();
2514 }
2515
2516 void SetExperiments(const Experiment* e, size_t count) {
2517   if (!e) {
2518     experiments = kExperiments;
2519     num_experiments = arraysize(kExperiments);
2520   } else {
2521     experiments = e;
2522     num_experiments = count;
2523   }
2524 }
2525
2526 const Experiment* GetExperiments(size_t* count) {
2527   *count = num_experiments;
2528   return experiments;
2529 }
2530
2531 }  // namespace testing
2532
2533 }  // namespace about_flags