src/chrome/browser/ui/browser_navigator.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/ui/browser_navigator.h"
   6
   7 #include <algorithm>
   8
   9 #include "base/command_line.h"
  10 #include "base/prefs/pref_service.h"
  11 #include "base/strings/stringprintf.h"
  12 #include "base/strings/utf_string_conversions.h"
  13 #include "chrome/browser/browser_about_handler.h"
  14 #include "chrome/browser/chrome_notification_types.h"
  15 #include "chrome/browser/extensions/tab_helper.h"
  16 #include "chrome/browser/prefs/incognito_mode_prefs.h"
  17 #include "chrome/browser/prerender/prerender_manager.h"
  18 #include "chrome/browser/prerender/prerender_manager_factory.h"
  19 #include "chrome/browser/prerender/prerender_util.h"
  20 #include "chrome/browser/profiles/profile.h"
  21 #include "chrome/browser/tab_contents/tab_util.h"
  22 #include "chrome/browser/ui/browser.h"
  23 #include "chrome/browser/ui/browser_finder.h"
  24 #include "chrome/browser/ui/browser_instant_controller.h"
  25 #include "chrome/browser/ui/browser_window.h"
  26 #include "chrome/browser/ui/host_desktop.h"
  27 #include "chrome/browser/ui/location_bar/location_bar.h"
  28 #include "chrome/browser/ui/search/instant_search_prerenderer.h"
  29 #include "chrome/browser/ui/singleton_tabs.h"
  30 #include "chrome/browser/ui/status_bubble.h"
  31 #include "chrome/browser/ui/tab_helpers.h"
  32 #include "chrome/browser/ui/tabs/tab_strip_model.h"
  33 #include "chrome/browser/web_applications/web_app.h"
  34 #include "chrome/common/pref_names.h"
  35 #include "chrome/common/url_constants.h"
  36 #include "components/google/core/browser/google_url_tracker.h"
  37 #include "content/public/browser/browser_url_handler.h"
  38 #include "content/public/browser/navigation_entry.h"
  39 #include "content/public/browser/notification_service.h"
  40 #include "content/public/browser/render_view_host.h"
  41 #include "content/public/browser/web_contents.h"
  42 #include "extensions/browser/extension_registry.h"
  43 #include "extensions/common/extension.h"
  44 #include "extensions/common/extension_set.h"
  45
  46 #if defined(USE_ASH)
  47 #include "chrome/browser/ui/ash/multi_user/multi_user_window_manager.h"
  48 #endif
  49 #if defined(USE_AURA)
  50 #include "ui/aura/window.h"
  51 #endif
  52
  53 using content::GlobalRequestID;
  54 using content::NavigationController;
  55 using content::WebContents;
  56
  57 class BrowserNavigatorWebContentsAdoption {
  58  public:
  59   static void AttachTabHelpers(content::WebContents* contents) {
  60     TabHelpers::AttachTabHelpers(contents);
  61   }
  62 };
  63
  64 namespace {
  65
  66 // Returns true if the specified Browser can open tabs. Not all Browsers support
  67 // multiple tabs, such as app frames and popups. This function returns false for
  68 // those types of Browser.
  69 bool WindowCanOpenTabs(Browser* browser) {
  70   return browser->CanSupportWindowFeature(Browser::FEATURE_TABSTRIP) ||
  71       browser->tab_strip_model()->empty();
  72 }
  73
  74 // Finds an existing Browser compatible with |profile|, making a new one if no
  75 // such Browser is located.
  76 Browser* GetOrCreateBrowser(Profile* profile,
  77                             chrome::HostDesktopType host_desktop_type) {
  78   Browser* browser = chrome::FindTabbedBrowser(profile, false,
  79                                                host_desktop_type);
  80   return browser ? browser : new Browser(
  81       Browser::CreateParams(profile, host_desktop_type));
  82 }
  83
  84 // Change some of the navigation parameters based on the particular URL.
  85 // Currently this applies to some chrome:// pages which we always want to open
  86 // in a non-incognito window. Note that even though a ChromeOS guest session is
  87 // technically an incognito window, these URLs are allowed.
  88 // Returns true on success. Otherwise, if changing params leads the browser into
  89 // an erroneous state, returns false.
  90 bool AdjustNavigateParamsForURL(chrome::NavigateParams* params) {
  91   if (params->target_contents != NULL ||
  92       chrome::IsURLAllowedInIncognito(params->url,
  93                                       params->initiating_profile) ||
  94       params->initiating_profile->IsGuestSession()) {
  95     return true;
  96   }
  97
  98   Profile* profile = params->initiating_profile;
  99
 100   if (profile->IsOffTheRecord() || params->disposition == OFF_THE_RECORD) {
 101     profile = profile->GetOriginalProfile();
 102
 103     // If incognito is forced, we punt.
 104     PrefService* prefs = profile->GetPrefs();
 105     if (prefs && IncognitoModePrefs::GetAvailability(prefs) ==
 106             IncognitoModePrefs::FORCED) {
 107       return false;
 108     }
 109
 110     params->disposition = SINGLETON_TAB;
 111     params->browser = GetOrCreateBrowser(profile, params->host_desktop_type);
 112     params->window_action = chrome::NavigateParams::SHOW_WINDOW;
 113   }
 114
 115   return true;
 116 }
 117
 118 // Returns a Browser that can host the navigation or tab addition specified in
 119 // |params|. This might just return the same Browser specified in |params|, or
 120 // some other if that Browser is deemed incompatible.
 121 Browser* GetBrowserForDisposition(chrome::NavigateParams* params) {
 122   // If no source WebContents was specified, we use the selected one from
 123   // the target browser. This must happen first, before
 124   // GetBrowserForDisposition() has a chance to replace |params->browser| with
 125   // another one.
 126   if (!params->source_contents && params->browser) {
 127     params->source_contents =
 128         params->browser->tab_strip_model()->GetActiveWebContents();
 129   }
 130
 131   Profile* profile = params->initiating_profile;
 132
 133   switch (params->disposition) {
 134     case CURRENT_TAB:
 135       if (params->browser)
 136         return params->browser;
 137       // Find a compatible window and re-execute this command in it. Otherwise
 138       // re-run with NEW_WINDOW.
 139       return GetOrCreateBrowser(profile, params->host_desktop_type);
 140     case SINGLETON_TAB:
 141     case NEW_FOREGROUND_TAB:
 142     case NEW_BACKGROUND_TAB:
 143       // See if we can open the tab in the window this navigator is bound to.
 144       if (params->browser && WindowCanOpenTabs(params->browser))
 145         return params->browser;
 146       // Find a compatible window and re-execute this command in it. Otherwise
 147       // re-run with NEW_WINDOW.
 148       return GetOrCreateBrowser(profile, params->host_desktop_type);
 149     case NEW_POPUP: {
 150       // Make a new popup window.
 151       // Coerce app-style if |source| represents an app.
 152       std::string app_name;
 153       if (!params->extension_app_id.empty()) {
 154         app_name = web_app::GenerateApplicationNameFromExtensionId(
 155             params->extension_app_id);
 156       } else if (params->browser && !params->browser->app_name().empty()) {
 157         app_name = params->browser->app_name();
 158       } else if (params->source_contents) {
 159         extensions::TabHelper* extensions_tab_helper =
 160             extensions::TabHelper::FromWebContents(params->source_contents);
 161         if (extensions_tab_helper && extensions_tab_helper->is_app()) {
 162           app_name = web_app::GenerateApplicationNameFromExtensionId(
 163               extensions_tab_helper->extension_app()->id());
 164         }
 165       }
 166       if (app_name.empty()) {
 167         Browser::CreateParams browser_params(
 168             Browser::TYPE_POPUP, profile, params->host_desktop_type);
 169         browser_params.trusted_source = params->trusted_source;
 170         browser_params.initial_bounds = params->window_bounds;
 171         return new Browser(browser_params);
 172       }
 173
 174       return new Browser(Browser::CreateParams::CreateForApp(
 175           app_name,
 176           params->trusted_source,
 177           params->window_bounds,
 178           profile,
 179           params->host_desktop_type));
 180     }
 181     case NEW_WINDOW: {
 182       // Make a new normal browser window.
 183       return new Browser(Browser::CreateParams(profile,
 184                                                params->host_desktop_type));
 185     }
 186     case OFF_THE_RECORD:
 187       // Make or find an incognito window.
 188       return GetOrCreateBrowser(profile->GetOffTheRecordProfile(),
 189                                 params->host_desktop_type);
 190     // The following types all result in no navigation.
 191     case SUPPRESS_OPEN:
 192     case SAVE_TO_DISK:
 193     case IGNORE_ACTION:
 194       return NULL;
 195     default:
 196       NOTREACHED();
 197   }
 198   return NULL;
 199 }
 200
 201 // Fix disposition and other parameter values depending on prevailing
 202 // conditions.
 203 void NormalizeDisposition(chrome::NavigateParams* params) {
 204   // Calculate the WindowOpenDisposition if necessary.
 205   if (params->browser->tab_strip_model()->empty() &&
 206       (params->disposition == NEW_BACKGROUND_TAB ||
 207        params->disposition == CURRENT_TAB ||
 208        params->disposition == SINGLETON_TAB)) {
 209     params->disposition = NEW_FOREGROUND_TAB;
 210   }
 211   if (params->browser->profile()->IsOffTheRecord() &&
 212       params->disposition == OFF_THE_RECORD) {
 213     params->disposition = NEW_FOREGROUND_TAB;
 214   }
 215   if (!params->source_contents && params->disposition == CURRENT_TAB)
 216     params->disposition = NEW_FOREGROUND_TAB;
 217
 218   switch (params->disposition) {
 219     case NEW_BACKGROUND_TAB:
 220       // Disposition trumps add types. ADD_ACTIVE is a default, so we need to
 221       // remove it if disposition implies the tab is going to open in the
 222       // background.
 223       params->tabstrip_add_types &= ~TabStripModel::ADD_ACTIVE;
 224       break;
 225
 226     case NEW_WINDOW:
 227     case NEW_POPUP:
 228       // Code that wants to open a new window typically expects it to be shown
 229       // automatically.
 230       if (params->window_action == chrome::NavigateParams::NO_ACTION)
 231         params->window_action = chrome::NavigateParams::SHOW_WINDOW;
 232       // Fall-through.
 233     case NEW_FOREGROUND_TAB:
 234     case SINGLETON_TAB:
 235       params->tabstrip_add_types |= TabStripModel::ADD_ACTIVE;
 236       break;
 237
 238     default:
 239       break;
 240   }
 241 }
 242
 243 // Obtain the profile used by the code that originated the Navigate() request.
 244 Profile* GetSourceProfile(chrome::NavigateParams* params) {
 245   if (params->source_contents) {
 246     return Profile::FromBrowserContext(
 247         params->source_contents->GetBrowserContext());
 248   }
 249
 250   return params->initiating_profile;
 251 }
 252
 253 void LoadURLInContents(WebContents* target_contents,
 254                        const GURL& url,
 255                        chrome::NavigateParams* params) {
 256   NavigationController::LoadURLParams load_url_params(url);
 257   load_url_params.referrer = params->referrer;
 258   load_url_params.frame_tree_node_id = params->frame_tree_node_id;
 259   load_url_params.redirect_chain = params->redirect_chain;
 260   load_url_params.transition_type = params->transition;
 261   load_url_params.extra_headers = params->extra_headers;
 262   load_url_params.should_replace_current_entry =
 263       params->should_replace_current_entry;
 264
 265   if (params->transferred_global_request_id != GlobalRequestID()) {
 266     load_url_params.is_renderer_initiated = params->is_renderer_initiated;
 267     load_url_params.transferred_global_request_id =
 268         params->transferred_global_request_id;
 269   } else if (params->is_renderer_initiated) {
 270     load_url_params.is_renderer_initiated = true;
 271   }
 272
 273   // Only allows the browser-initiated navigation to use POST.
 274   if (params->uses_post && !params->is_renderer_initiated) {
 275     load_url_params.load_type =
 276         NavigationController::LOAD_TYPE_BROWSER_INITIATED_HTTP_POST;
 277     load_url_params.browser_initiated_post_data =
 278         params->browser_initiated_post_data;
 279   }
 280   target_contents->GetController().LoadURLWithParams(load_url_params);
 281 }
 282
 283 // This class makes sure the Browser object held in |params| is made visible
 284 // by the time it goes out of scope, provided |params| wants it to be shown.
 285 class ScopedBrowserShower {
 286  public:
 287   explicit ScopedBrowserShower(chrome::NavigateParams* params)
 288       : params_(params) {
 289   }
 290   ~ScopedBrowserShower() {
 291     if (params_->window_action == chrome::NavigateParams::SHOW_WINDOW_INACTIVE)
 292       params_->browser->window()->ShowInactive();
 293     else if (params_->window_action == chrome::NavigateParams::SHOW_WINDOW)
 294       params_->browser->window()->Show();
 295   }
 296  private:
 297   chrome::NavigateParams* params_;
 298   DISALLOW_COPY_AND_ASSIGN(ScopedBrowserShower);
 299 };
 300
 301 // This class manages the lifetime of a WebContents created by the
 302 // Navigate() function. When Navigate() creates a WebContents for a URL,
 303 // an instance of this class takes ownership of it via TakeOwnership() until the
 304 // WebContents is added to a tab strip at which time ownership is
 305 // relinquished via ReleaseOwnership(). If this object goes out of scope without
 306 // being added to a tab strip, the created WebContents is deleted to
 307 // avoid a leak and the params->target_contents field is set to NULL.
 308 class ScopedTargetContentsOwner {
 309  public:
 310   explicit ScopedTargetContentsOwner(chrome::NavigateParams* params)
 311       : params_(params) {
 312   }
 313   ~ScopedTargetContentsOwner() {
 314     if (target_contents_owner_.get())
 315       params_->target_contents = NULL;
 316   }
 317
 318   // Assumes ownership of |params_|' target_contents until ReleaseOwnership
 319   // is called.
 320   void TakeOwnership() {
 321     target_contents_owner_.reset(params_->target_contents);
 322   }
 323
 324   // Relinquishes ownership of |params_|' target_contents.
 325   WebContents* ReleaseOwnership() {
 326     return target_contents_owner_.release();
 327   }
 328
 329  private:
 330   chrome::NavigateParams* params_;
 331   scoped_ptr<WebContents> target_contents_owner_;
 332   DISALLOW_COPY_AND_ASSIGN(ScopedTargetContentsOwner);
 333 };
 334
 335 content::WebContents* CreateTargetContents(const chrome::NavigateParams& params,
 336                                            const GURL& url) {
 337   WebContents::CreateParams create_params(
 338       params.browser->profile(),
 339       tab_util::GetSiteInstanceForNewTab(params.browser->profile(), url));
 340   if (params.source_contents) {
 341     create_params.initial_size =
 342         params.source_contents->GetContainerBounds().size();
 343     if (params.should_set_opener)
 344       create_params.opener = params.source_contents;
 345   }
 346   if (params.disposition == NEW_BACKGROUND_TAB)
 347     create_params.initially_hidden = true;
 348
 349 #if defined(USE_AURA)
 350   if (params.browser->window() &&
 351       params.browser->window()->GetNativeWindow()) {
 352     create_params.context =
 353         params.browser->window()->GetNativeWindow();
 354   }
 355 #endif
 356
 357   WebContents* target_contents = WebContents::Create(create_params);
 358
 359   // New tabs can have WebUI URLs that will make calls back to arbitrary
 360   // tab helpers, so the entire set of tab helpers needs to be set up
 361   // immediately.
 362   BrowserNavigatorWebContentsAdoption::AttachTabHelpers(target_contents);
 363   extensions::TabHelper::FromWebContents(target_contents)->
 364       SetExtensionAppById(params.extension_app_id);
 365   return target_contents;
 366 }
 367
 368 // If a prerendered page exists for |url|, replace the page at
 369 // |params->target_contents| with it and update to point to the swapped-in
 370 // WebContents.
 371 bool SwapInPrerender(const GURL& url, chrome::NavigateParams* params) {
 372   Profile* profile =
 373       Profile::FromBrowserContext(params->target_contents->GetBrowserContext());
 374   InstantSearchPrerenderer* prerenderer =
 375       InstantSearchPrerenderer::GetForProfile(profile);
 376   if (prerenderer && prerenderer->UsePrerenderedPage(url, params))
 377     return true;
 378
 379   prerender::PrerenderManager* prerender_manager =
 380       prerender::PrerenderManagerFactory::GetForProfile(profile);
 381   return prerender_manager &&
 382       prerender_manager->MaybeUsePrerenderedPage(url, params);
 383 }
 384
 385 chrome::HostDesktopType GetHostDesktop(Browser* browser) {
 386   if (browser)
 387     return browser->host_desktop_type();
 388   return chrome::GetActiveDesktop();
 389 }
 390
 391 }  // namespace
 392
 393 namespace chrome {
 394
 395 NavigateParams::NavigateParams(Browser* a_browser,
 396                                const GURL& a_url,
 397                                content::PageTransition a_transition)
 398     : url(a_url),
 399       frame_tree_node_id(-1),
 400       uses_post(false),
 401       target_contents(NULL),
 402       source_contents(NULL),
 403       disposition(CURRENT_TAB),
 404       trusted_source(false),
 405       transition(a_transition),
 406       is_renderer_initiated(false),
 407       tabstrip_index(-1),
 408       tabstrip_add_types(TabStripModel::ADD_ACTIVE),
 409       window_action(NO_ACTION),
 410       user_gesture(true),
 411       path_behavior(RESPECT),
 412       ref_behavior(IGNORE_REF),
 413       browser(a_browser),
 414       initiating_profile(NULL),
 415       host_desktop_type(GetHostDesktop(a_browser)),
 416       should_replace_current_entry(false),
 417       should_set_opener(false) {
 418 }
 419
 420 NavigateParams::NavigateParams(Browser* a_browser,
 421                                WebContents* a_target_contents)
 422     : frame_tree_node_id(-1),
 423       uses_post(false),
 424       target_contents(a_target_contents),
 425       source_contents(NULL),
 426       disposition(CURRENT_TAB),
 427       trusted_source(false),
 428       transition(content::PAGE_TRANSITION_LINK),
 429       is_renderer_initiated(false),
 430       tabstrip_index(-1),
 431       tabstrip_add_types(TabStripModel::ADD_ACTIVE),
 432       window_action(NO_ACTION),
 433       user_gesture(true),
 434       path_behavior(RESPECT),
 435       ref_behavior(IGNORE_REF),
 436       browser(a_browser),
 437       initiating_profile(NULL),
 438       host_desktop_type(GetHostDesktop(a_browser)),
 439       should_replace_current_entry(false),
 440       should_set_opener(false) {
 441 }
 442
 443 NavigateParams::NavigateParams(Profile* a_profile,
 444                                const GURL& a_url,
 445                                content::PageTransition a_transition)
 446     : url(a_url),
 447       frame_tree_node_id(-1),
 448       uses_post(false),
 449       target_contents(NULL),
 450       source_contents(NULL),
 451       disposition(NEW_FOREGROUND_TAB),
 452       trusted_source(false),
 453       transition(a_transition),
 454       is_renderer_initiated(false),
 455       tabstrip_index(-1),
 456       tabstrip_add_types(TabStripModel::ADD_ACTIVE),
 457       window_action(SHOW_WINDOW),
 458       user_gesture(true),
 459       path_behavior(RESPECT),
 460       ref_behavior(IGNORE_REF),
 461       browser(NULL),
 462       initiating_profile(a_profile),
 463       host_desktop_type(chrome::GetActiveDesktop()),
 464       should_replace_current_entry(false),
 465       should_set_opener(false) {
 466 }
 467
 468 NavigateParams::~NavigateParams() {}
 469
 470 void FillNavigateParamsFromOpenURLParams(chrome::NavigateParams* nav_params,
 471                                          const content::OpenURLParams& params) {
 472   nav_params->referrer = params.referrer;
 473   nav_params->frame_tree_node_id = params.frame_tree_node_id;
 474   nav_params->redirect_chain = params.redirect_chain;
 475   nav_params->extra_headers = params.extra_headers;
 476   nav_params->disposition = params.disposition;
 477   nav_params->trusted_source = false;
 478   nav_params->is_renderer_initiated = params.is_renderer_initiated;
 479   nav_params->transferred_global_request_id =
 480       params.transferred_global_request_id;
 481   nav_params->should_replace_current_entry =
 482       params.should_replace_current_entry;
 483   nav_params->uses_post = params.uses_post;
 484   nav_params->browser_initiated_post_data = params.browser_initiated_post_data;
 485 }
 486
 487 void Navigate(NavigateParams* params) {
 488   Browser* source_browser = params->browser;
 489   if (source_browser)
 490     params->initiating_profile = source_browser->profile();
 491   DCHECK(params->initiating_profile);
 492
 493   if (!AdjustNavigateParamsForURL(params))
 494     return;
 495
 496   const extensions::Extension* extension =
 497     extensions::ExtensionRegistry::Get(params->initiating_profile)->
 498         enabled_extensions().GetExtensionOrAppByURL(params->url);
 499   // Platform apps cannot navigate. Block the request.
 500   if (extension && extension->is_platform_app())
 501     params->url = GURL(chrome::kExtensionInvalidRequestURL);
 502
 503   // The browser window may want to adjust the disposition.
 504   if (params->disposition == NEW_POPUP &&
 505       source_browser &&
 506       source_browser->window()) {
 507     params->disposition =
 508         source_browser->window()->GetDispositionForPopupBounds(
 509             params->window_bounds);
 510   }
 511
 512   params->browser = GetBrowserForDisposition(params);
 513   if (!params->browser)
 514     return;
 515
 516 #if defined(USE_ASH)
 517   if (source_browser && source_browser != params->browser) {
 518     // When the newly created browser was spawned by a browser which visits
 519     // another user's desktop, it should be shown on the same desktop as the
 520     // originating one. (This is part of the desktop separation per profile).
 521     MultiUserWindowManager* manager = MultiUserWindowManager::GetInstance();
 522     // Some unit tests have no manager instantiated.
 523     if (manager) {
 524       aura::Window* src_window = source_browser->window()->GetNativeWindow();
 525       aura::Window* new_window = params->browser->window()->GetNativeWindow();
 526       const std::string& src_user =
 527           manager->GetUserPresentingWindow(src_window);
 528       if (src_user != manager->GetUserPresentingWindow(new_window)) {
 529         // Once the window gets presented, it should be shown on the same
 530         // desktop as the desktop of the creating browser. Note that this
 531         // command will not show the window if it wasn't shown yet by the
 532         // browser creation.
 533         manager->ShowWindowForUser(new_window, src_user);
 534       }
 535     }
 536   }
 537 #endif
 538
 539   // Navigate() must not return early after this point.
 540
 541   if (GetSourceProfile(params) != params->browser->profile()) {
 542     // A tab is being opened from a link from a different profile, we must reset
 543     // source information that may cause state to be shared.
 544     params->source_contents = NULL;
 545     params->referrer = content::Referrer();
 546   }
 547
 548   // Make sure the Browser is shown if params call for it.
 549   ScopedBrowserShower shower(params);
 550
 551   // Makes sure any WebContents created by this function is destroyed if
 552   // not properly added to a tab strip.
 553   ScopedTargetContentsOwner target_contents_owner(params);
 554
 555   // Some dispositions need coercion to base types.
 556   NormalizeDisposition(params);
 557
 558   // If a new window has been created, it needs to be shown.
 559   if (params->window_action == NavigateParams::NO_ACTION &&
 560       source_browser != params->browser &&
 561       params->browser->tab_strip_model()->empty()) {
 562     params->window_action = NavigateParams::SHOW_WINDOW;
 563   }
 564
 565   // If we create a popup window from a non user-gesture, don't activate it.
 566   if (params->window_action == NavigateParams::SHOW_WINDOW &&
 567       params->disposition == NEW_POPUP &&
 568       params->user_gesture == false) {
 569     params->window_action = NavigateParams::SHOW_WINDOW_INACTIVE;
 570   }
 571
 572   // Determine if the navigation was user initiated. If it was, we need to
 573   // inform the target WebContents, and we may need to update the UI.
 574   content::PageTransition base_transition =
 575       content::PageTransitionStripQualifier(params->transition);
 576   bool user_initiated =
 577       params->transition & content::PAGE_TRANSITION_FROM_ADDRESS_BAR ||
 578       base_transition == content::PAGE_TRANSITION_TYPED ||
 579       base_transition == content::PAGE_TRANSITION_AUTO_BOOKMARK ||
 580       base_transition == content::PAGE_TRANSITION_GENERATED ||
 581       base_transition == content::PAGE_TRANSITION_AUTO_TOPLEVEL ||
 582       base_transition == content::PAGE_TRANSITION_RELOAD ||
 583       base_transition == content::PAGE_TRANSITION_KEYWORD;
 584
 585   // Check if this is a singleton tab that already exists
 586   int singleton_index = chrome::GetIndexOfSingletonTab(params);
 587
 588   // Did we use a prerender?
 589   bool swapped_in_prerender = false;
 590
 591   // If no target WebContents was specified, we need to construct one if
 592   // we are supposed to target a new tab; unless it's a singleton that already
 593   // exists.
 594   if (!params->target_contents && singleton_index < 0) {
 595     DCHECK(!params->url.is_empty());
 596     if (params->disposition != CURRENT_TAB) {
 597       params->target_contents = CreateTargetContents(*params, params->url);
 598
 599       // This function takes ownership of |params->target_contents| until it
 600       // is added to a TabStripModel.
 601       target_contents_owner.TakeOwnership();
 602     } else {
 603       // ... otherwise if we're loading in the current tab, the target is the
 604       // same as the source.
 605       DCHECK(params->source_contents);
 606       params->target_contents = params->source_contents;
 607     }
 608
 609     // Note: at this point, if |params->disposition| is not CURRENT_TAB,
 610     // |params->target_contents| has not been attached to a Browser yet. (That
 611     // happens later in this function.) However, in that case, the
 612     // sessionStorage namespace could not match, so prerender will use the
 613     // asynchronous codepath and still swap.
 614     DCHECK(params->target_contents);
 615     swapped_in_prerender = SwapInPrerender(params->url, params);
 616
 617     if (user_initiated)
 618       params->target_contents->UserGestureDone();
 619
 620     if (!swapped_in_prerender) {
 621       // Try to handle non-navigational URLs that popup dialogs and such, these
 622       // should not actually navigate.
 623       if (!HandleNonNavigationAboutURL(params->url)) {
 624         // Perform the actual navigation, tracking whether it came from the
 625         // renderer.
 626
 627         LoadURLInContents(params->target_contents, params->url, params);
 628         // For prerender bookkeeping purposes, record that this pending navigate
 629         // originated from chrome::Navigate.
 630         content::NavigationEntry* entry =
 631             params->target_contents->GetController().GetPendingEntry();
 632         if (entry)
 633           entry->SetExtraData(prerender::kChromeNavigateExtraDataKey,
 634                               base::string16());
 635       }
 636     }
 637   } else {
 638     // |target_contents| was specified non-NULL, and so we assume it has already
 639     // been navigated appropriately. We need to do nothing more other than
 640     // add it to the appropriate tabstrip.
 641   }
 642
 643   // If the user navigated from the omnibox, and the selected tab is going to
 644   // lose focus, then make sure the focus for the source tab goes away from the
 645   // omnibox.
 646   if (params->source_contents &&
 647       (params->disposition == NEW_FOREGROUND_TAB ||
 648        params->disposition == NEW_WINDOW) &&
 649       (params->tabstrip_add_types & TabStripModel::ADD_INHERIT_OPENER))
 650     params->source_contents->Focus();
 651
 652   if (params->source_contents == params->target_contents ||
 653       (swapped_in_prerender && params->disposition == CURRENT_TAB)) {
 654     // The navigation occurred in the source tab.
 655     params->browser->UpdateUIForNavigationInTab(params->target_contents,
 656                                                 params->transition,
 657                                                 user_initiated);
 658   } else if (singleton_index == -1) {
 659     // If some non-default value is set for the index, we should tell the
 660     // TabStripModel to respect it.
 661     if (params->tabstrip_index != -1)
 662       params->tabstrip_add_types |= TabStripModel::ADD_FORCE_INDEX;
 663
 664     // The navigation should insert a new tab into the target Browser.
 665     params->browser->tab_strip_model()->AddWebContents(
 666         params->target_contents,
 667         params->tabstrip_index,
 668         params->transition,
 669         params->tabstrip_add_types);
 670     // Now that the |params->target_contents| is safely owned by the target
 671     // Browser's TabStripModel, we can release ownership.
 672     target_contents_owner.ReleaseOwnership();
 673   }
 674
 675   if (singleton_index >= 0) {
 676     WebContents* target =
 677         params->browser->tab_strip_model()->GetWebContentsAt(singleton_index);
 678
 679     if (target->IsCrashed()) {
 680       target->GetController().Reload(true);
 681     } else if (params->path_behavior == NavigateParams::IGNORE_AND_NAVIGATE &&
 682         target->GetURL() != params->url) {
 683       LoadURLInContents(target, params->url, params);
 684       // For prerender bookkeeping purposes, record that this pending navigate
 685       // originated from chrome::Navigate.
 686       content::NavigationEntry* entry =
 687           target->GetController().GetPendingEntry();
 688       if (entry)
 689         entry->SetExtraData(prerender::kChromeNavigateExtraDataKey,
 690                             base::string16());
 691     }
 692
 693     // If the singleton tab isn't already selected, select it.
 694     if (params->source_contents != params->target_contents) {
 695       params->browser->tab_strip_model()->ActivateTabAt(singleton_index,
 696                                                         user_initiated);
 697     }
 698   }
 699
 700   if (params->disposition != CURRENT_TAB) {
 701     content::NotificationService::current()->Notify(
 702         chrome::NOTIFICATION_TAB_ADDED,
 703         content::Source<content::WebContentsDelegate>(params->browser),
 704         content::Details<WebContents>(params->target_contents));
 705   }
 706 }
 707
 708 bool IsURLAllowedInIncognito(const GURL& url,
 709                              content::BrowserContext* browser_context) {
 710   if (url.scheme() == content::kViewSourceScheme) {
 711     // A view-source URL is allowed in incognito mode only if the URL itself
 712     // is allowed in incognito mode. Remove the "view-source:" from the start
 713     // of the URL and validate the rest.
 714     std::string stripped_spec = url.spec();
 715     DCHECK_GT(stripped_spec.size(), strlen(content::kViewSourceScheme));
 716     stripped_spec.erase(0, strlen(content::kViewSourceScheme) + 1);
 717     GURL stripped_url(stripped_spec);
 718     return stripped_url.is_valid() &&
 719         IsURLAllowedInIncognito(stripped_url, browser_context);
 720   }
 721   // Most URLs are allowed in incognito; the following are exceptions.
 722   // chrome://extensions is on the list because it redirects to
 723   // chrome://settings.
 724   if (url.scheme() == content::kChromeUIScheme &&
 725       (url.host() == chrome::kChromeUISettingsHost ||
 726        url.host() == chrome::kChromeUISettingsFrameHost ||
 727        url.host() == chrome::kChromeUIExtensionsHost ||
 728        url.host() == chrome::kChromeUIBookmarksHost ||
 729 #if !defined(OS_CHROMEOS)
 730        url.host() == chrome::kChromeUIChromeSigninHost ||
 731 #endif
 732        url.host() == chrome::kChromeUIUberHost ||
 733        url.host() == chrome::kChromeUIThumbnailHost ||
 734        url.host() == chrome::kChromeUIThumbnailHost2 ||
 735        url.host() == chrome::kChromeUIThumbnailListHost ||
 736        url.host() == chrome::kChromeUISuggestionsHost ||
 737        url.host() == chrome::kChromeUIDevicesHost ||
 738        url.host() == chrome::kChromeUIVoiceSearchHost)) {
 739     return false;
 740   }
 741
 742   if (url.scheme() == chrome::kChromeSearchScheme &&
 743       (url.host() == chrome::kChromeUIThumbnailHost ||
 744        url.host() == chrome::kChromeUIThumbnailHost2 ||
 745        url.host() == chrome::kChromeUIThumbnailListHost ||
 746        url.host() == chrome::kChromeUISuggestionsHost)) {
 747     return false;
 748   }
 749
 750   GURL rewritten_url = url;
 751   bool reverse_on_redirect = false;
 752   content::BrowserURLHandler::GetInstance()->RewriteURLIfNecessary(
 753       &rewritten_url, browser_context, &reverse_on_redirect);
 754
 755   // Some URLs are mapped to uber subpages. Do not allow them in incognito.
 756   return !(rewritten_url.scheme() == content::kChromeUIScheme &&
 757            rewritten_url.host() == chrome::kChromeUIUberHost);
 758 }
 759
 760 }  // namespace chrome