Expose/test String.Create span-based method (dotnet/corefx#23872)

* Expose/test String.Create span-based method

* Address PR feedback

Commit migrated from https://github.com/dotnet/corefx/commit/8cc35f2e402b77fa666e1362696df735a9529027

Merge pull request dotnet/corefx#24187 from dotnet-maestro-bot/master-UpdateDependencies

Update CoreClr, CoreSetup, ProjectNTfs, ProjectNTfsTestILC, Standard to preview1-25720-03, preview1-25719-04, beta-25721-01, beta-25721-01, preview1-25721-01, respectively (master)

Commit migrated from https://github.com/dotnet/corefx/commit/6ae4ff347a28f80891c2a96f5d0455c54e45c804

Merge pull request dotnet/corefx#24151 from qmfrederik/drawing/metafile-mono-tests

Add unit tests for System.Drawing.Imaging.Metafile based on Mono's unit tests

Commit migrated from https://github.com/dotnet/corefx/commit/95f68c449ece32f30fa19f08c97c3d2fcff69d5c

Workaround libgdiplus glitches

Don't test metafileHeader.Bounds when using libgdiplus.
Don't test metafile.GetBounds on Unix, force MetafileHeader.Bounds to return an empty rectangle when MetafileSize == 0
Don't validate graphicsUnit on Unix.

Commit migrated from https://github.com/dotnet/corefx/commit/abfd51d0f2019b204a6d29836381d183f3390d2e

Remove X11 dependency for tests which are enabled on Unix.

Commit migrated from https://github.com/dotnet/corefx/commit/8f3f06625346bbb0b39a75105024d64a4139cd26

Remove duplicate tests, fix typo

Commit migrated from https://github.com/dotnet/corefx/commit/d284084addaee43add43a0a31272352eb25aeb11

PR feedback

Commit migrated from https://github.com/dotnet/corefx/commit/8e151ad37220a64e122d5406eee6935e14595e30

Assert.False(Object.ReferenceEquals => Assert.NotSame

Commit migrated from https://github.com/dotnet/corefx/commit/966a10e90ad495e0b0e57895005b0fe448bfe151

Don't catch an ArgumentException just to get a NullReferenceException instead.

Commit migrated from https://github.com/dotnet/corefx/commit/e12abadaaed28128232e1972d1aa94a467ab11ac

Simplify tests, remove duplicate test

Commit migrated from https://github.com/dotnet/corefx/commit/8ffcab504ef7ebe503a15ed18d994774d7fb3bb2

Fix Metafile exception behavior

Commit migrated from https://github.com/dotnet/corefx/commit/cb271af10e2f1cee2e5e02ee4d860979968f2b1c

Update project file

Commit migrated from https://github.com/dotnet/corefx/commit/b138dba1a93207dee4bc63e0a378c96027b5a1c6

Rationalize using statements

Commit migrated from https://github.com/dotnet/corefx/commit/a82017b65894c66980c4c6524ac610ee23f19cb3

MetafileTests: Remove duplicates, and re-enable tests on Unix which are now working.
Delete duplicate MetaHeadertests

Commit migrated from https://github.com/dotnet/corefx/commit/367ab73d9d57186dd3f090da6a0000756186a93d

Update project file

Commit migrated from https://github.com/dotnet/corefx/commit/af4e3dfeca56dff633f9b58de9226ec87a2e3980

Add Metafile and MetaHeader tests based on Mono's System.Drawing unit tests

Commit migrated from https://github.com/dotnet/corefx/commit/22f2ee1bb825065536ae9760bd26e865461bb409

Merge pull request dotnet/corefx#24194 from mellinoe/system.drawing-finish-consolidation

[Drawing] Move remaining "Unix" files into regular directory structure

Commit migrated from https://github.com/dotnet/corefx/commit/0f14a8cd6b06bcba290e796a641d0acd6a7706b1

Change AsSpan to property Span and rename AsMemory to Memory

Commit migrated from https://github.com/dotnet/corefx/commit/786195a51ca0b751f5aec127faf655fe358c6993

Merge pull request dotnet/corefx#24183 from maryamariyan/odbc-temp

Adding System.Data.Odbc package and including in metapackage

Commit migrated from https://github.com/dotnet/corefx/commit/a7575a74be9a3e7ea161298acc6af477f38b7161

[Drawing] Move remaining "Unix" files into regular directory structure

* As part of this, the "Windows" version of ImageFormat.cs is now being
  used everywhere. This file just contains a bunch of GUID's that are not
  platform-specific in any way.

Commit migrated from https://github.com/dotnet/corefx/commit/74a3d566ecee00e442f05157fd6952f389ff08e2

Merge pull request dotnet/corefx#24184 from hughbe/brush-mt

Fix MultiplyTransform with a disposed brush

Commit migrated from https://github.com/dotnet/corefx/commit/eb851a2b0243859be21e0d9d6fc3c4a4c5f9c7c5

CoreFx dotnet/corefx#22406 Span based APIs - Text Reader Writer (dotnet/corefx#23786)

Commit migrated from https://github.com/dotnet/corefx/commit/c09ce65e6de10572abe4058f514338db2ef47ed9

Update CoreClr, CoreSetup, ProjectNTfs, ProjectNTfsTestILC, Standard to preview1-25720-03, preview1-25719-04, beta-25721-01, beta-25721-01, preview1-25721-01, respectively

Commit migrated from https://github.com/dotnet/corefx/commit/04dd4993ae020bafd633c9f5b1a49fcf1cf882a7

Fix for 2nd Connection hangs in Mirroring Environment (dotnet/corefx#24181)

Commit migrated from https://github.com/dotnet/corefx/commit/dd48b05151c56fcf92cacc071f80fd39c099cadc

Fix MultiplyTransform with a disposed brush

Commit migrated from https://github.com/dotnet/corefx/commit/cde07104a9369b2542098e426bc5fa399741272b

Adding System.Data.Odbc package and including in metapackage

Commit migrated from https://github.com/dotnet/corefx/commit/c895e10bfce739bcc77b4aead77f911dec6774d6

Remove unused FEATURE_RANDOMIZED_STRING_HASHING (dotnet/corefx#24178)

Commit migrated from https://github.com/dotnet/corefx/commit/b73daf35e0188c1202be727806dede253f3b4332

Merge pull request dotnet/corefx#24150 from qmfrederik/drawing/graphics-mono-tests

System.Drawing - Add Graphics tests based on Mono's test suite

Commit migrated from https://github.com/dotnet/corefx/commit/de59a4244556433aee39faba347402a30801f03c

Fix memory map imports (dotnet/corefx#24176)

* Fix memory map imports

Imports lost the last error attribute. Add it back and change the results to be the more correct "bool". Tweak the usage based on the new return type.

dotnet/corefx#24159

* Move spin wait

Commit migrated from https://github.com/dotnet/corefx/commit/b0a91f4a19784d87f51c678baadbfe266440f4c0

Merge pull request dotnet/corefx#23932 from JonHanna/biginteger_reach_minvalue_opt

Make BigInteger ctor opt path for == int.MinValue reachable.

Commit migrated from https://github.com/dotnet/corefx/commit/2a650d568dba1724b0fe136af6714d7133aab745

Merge pull request dotnet/corefx#24166 from hughbe/hatchbrush-fixes

Fix HatchBrush constructor validation, renable more passing tests on Unix

Commit migrated from https://github.com/dotnet/corefx/commit/aa1ff5efc54ee788687c8a912afe2937f4538858

Merge pull request dotnet/corefx#24086 from mellinoe/system.drawing-mono-win32-cleanup

Consolidate more code in the "System.Drawing" namespace.

Commit migrated from https://github.com/dotnet/corefx/commit/dce54eac6369631bf9e0af274cb0abd484edb331

PR feedback

Commit migrated from https://github.com/dotnet/corefx/commit/5d1ee6567cd0cae92b66a49168b5bfdcb91a53f7

Address PR feedback

Commit migrated from https://github.com/dotnet/corefx/commit/5fbce4b45c94c6f7246d9c58e28c6761dbee7dd9

Merge pull request dotnet/corefx#24170 from danmosemsft/fix.threadsleep

Remove Thread.Sleep workaround

Commit migrated from https://github.com/dotnet/corefx/commit/0b2dc05d223938570724da180a3fadbbb0a9052d

Update BuildTools to prerelease-02020-01 (dotnet/corefx#24172)

Commit migrated from https://github.com/dotnet/corefx/commit/933ffa4d80a4183951deddfbc4510a94fb12b3f1

Remove Thread.Sleep workaround

Commit migrated from https://github.com/dotnet/corefx/commit/7af1113607a94a22fa2e340863408b90211c2f53

Renable some already passing tests

Commit migrated from https://github.com/dotnet/corefx/commit/fa1422e4b4c608be2b98542736776de1e10c0460

Remove references to historical Mono bug IDs

Commit migrated from https://github.com/dotnet/corefx/commit/822338b447ed336c5e60d23066f1fe347909abe0

Delete accidentally duplicated HatchBrush tests in LinearGradientBrushTests

Commit migrated from https://github.com/dotnet/corefx/commit/c8767bc47a4a365ad1fc362733b9ba0c36b3707a

Validate HatchStyle passed to HatchBrush ctor

Commit migrated from https://github.com/dotnet/corefx/commit/6406e382af893765a21eab1d2e11431cb838afde

Cleanup - Add/simplify using statements of disposable resources (Graphics, Bitmap)

Commit migrated from https://github.com/dotnet/corefx/commit/0b5b1e4113ee848041c89256589d6aec5b9672b8

Bump System.Drawing.Common.TestData to 1.0.6 (dotnet/corefx#24149)

* Bump system.drawing.common.testdata to 1.0.6

* Fix path to test data

* Fix whitespace

Commit migrated from https://github.com/dotnet/corefx/commit/c4e03f00fe667aed5a4a79a4b039a8c842fdfcc4

Add an error code fixup to Bitmap.Unix.cs to match Windows.

Commit migrated from https://github.com/dotnet/corefx/commit/a4e548c30693ab6e7922a2d8b1444847265fc1f1

Fix multiplying TextureBrush with a disposed matrix on Unix (dotnet/corefx#24109)

* Fix multiplying TextureBrush with a disposed matrix on Unix

* Enable another passing test

* Fix accidentally committed file

Commit migrated from https://github.com/dotnet/corefx/commit/15f9a31fd45f9a7d667765ef08ecfd1cefddde3a

Remove duplicate tests.

Commit migrated from https://github.com/dotnet/corefx/commit/6cdccce2ef06ae448aa99ecface2085157b0c72d

Add conditionals for recent versions of mono

Commit migrated from https://github.com/dotnet/corefx/commit/a379e9cff54b001eecf37c4653de88b5142c1363

Tiny bit of code cleanup

Commit migrated from https://github.com/dotnet/corefx/commit/b51ddcb89f66dfde8e33061ac030b01b03628947

Consolidate more code in the "System.Drawing" namespace.

* Remove all remaining Win32 codepaths from the mono codebase. All of this
  code now implicitly assumes that it will be run on a Unix platform.
* Consolidate the rest of the gdipFunctions.cs file into Gdip.cs and
  GdipNative.Unix.cs
* Consolidate the GraphicsUnit and ImageType enumerations -- they were
  duplicated.
* Remove the mono Status enum and use the Windows constants instead in all
  Unix code.
* Move all files into the regular directory structure. Suffix them with
  ".Unix" and ".Windows" when there are collisions.

Commit migrated from https://github.com/dotnet/corefx/commit/98a954b18bc3facbfd19ae35481788c738f6ae62

Add GraphicsTests based on Mono's test suite.

Commit migrated from https://github.com/dotnet/corefx/commit/a44c20c316e9b847e74252c6644d7ad375df3661

Fix whitespace

Commit migrated from https://github.com/dotnet/corefx/commit/4075ec559ca8f4f203b29fd279c1f000eca2b997

Fix path to test data

Commit migrated from https://github.com/dotnet/corefx/commit/4f06af813b0687dad8566077b13f245eeaa7ea34

Update BuildTools to prerelease-02019-02 (dotnet/corefx#24146)

Commit migrated from https://github.com/dotnet/corefx/commit/014e831ae385e0daff36895f7e9a36839057a02d

Bump system.drawing.common.testdata to 1.0.6

Commit migrated from https://github.com/dotnet/corefx/commit/8020b147e6edddc8e7657fd91db780c4c6b07ab6

Remove invalid NameResolution tests (dotnet/corefx#24147)

The Dns_GetHostEntryAsync_* are fundamentially invalid because it's
possible for the broadcast address, 255.255.255.255, to have an DNS
mapping via manually modifying the hosts file.  This was actually
happening on Mac systems as well as an virtual environment running on
top of that (i.e. Windows on Parallels).

Ref:
https://github.com/dotnet/corefx/issues/23992#issuecomment-330250642

Contributes to dotnet/corefx#23992

Commit migrated from https://github.com/dotnet/corefx/commit/e33bee86b4777a2de04bd0dc5b6e9e918bac302a

System.Drawing: Throw ArgumentNullException on Unix as well (dotnet/corefx#24140)

* Throw ArgumentNullException when stream is null

* Throw ArgumentNullException when stream is null

Commit migrated from https://github.com/dotnet/corefx/commit/7099d7e7e2fc0e369f29ddc6e53673f73b619cb6

Marking {ReadOnly}Span as readonly structs (dotnet/corefx#23908)

* Marking {ReadOnly}Span as readonly structs, fixing issue dotnet/corefx#23809

* Adding readonly attributes to reference assemblies.

* Using "readonly ref" keyword instead of attributes.

* Adding a LangVersion 7.2 property

Commit migrated from https://github.com/dotnet/corefx/commit/6542f6466c929f5590308f0a9150f1aed7b52f49

Fixed compile warning/error on FreeBSD (dotnet/corefx#24141)

Commit migrated from https://github.com/dotnet/corefx/commit/b1ceb5357f24302f0b5ba0c35be70c7e8cdcfd51

Update BuildTools, CoreClr, CoreFx, CoreSetup, Standard to prerelease-02019-01, preview1-25718-02, preview1-25718-03, preview1-25717-02, preview1-25718-01, respectively (dotnet/corefx#24075)

Commit migrated from https://github.com/dotnet/corefx/commit/996ddfd4489436907ef4e282cbfb99f9eb03f00c

Merge pull request dotnet/corefx#24131 from mellinoe/revert-remove-drawing

Revert "Remove System.Drawing.Common from the netfx compat package

Commit migrated from https://github.com/dotnet/corefx/commit/5846dbe88490a7685f29784277dd2e599d7cb366

Revert "Remove System.Drawing.Common from the netfx compat package (temporary)."

This reverts commit dotnet/corefx@f6b0fbd09b8a6dc312e55644a1353cea0fb2936d.

Commit migrated from https://github.com/dotnet/corefx/commit/f41685e2d4bcb350fd5129391e23e82a51523547

Disable Test_Write_Metric_eventListener on UWP. (dotnet/corefx#24127)

Commit migrated from https://github.com/dotnet/corefx/commit/72d769c5cf89ab7875cd4fecf4461c46a4b8cbcd

Fix instantiating PrincipleContext  with Domain type (dotnet/corefx#24122)

* Fix instantiating PrincipleContext  with Domain type

* Enhancement

Commit migrated from https://github.com/dotnet/corefx/commit/adde5513211d944e937449d01f45a823ebd2a469

Stop running Math.Clamp tests on UAP as API is not there (dotnet/corefx#24125)

* Stop running Math.Clamp tests on UAP as API is not there

* Disable only for AOT

Commit migrated from https://github.com/dotnet/corefx/commit/03e4e25a1209033f0a82f4f24660ba7cb1db5049

Merge pull request dotnet/corefx#24130 from mellinoe/netfx-compat-remove-drawing

Remove System.Drawing.Common from the netfx compat package (temporary).

Commit migrated from https://github.com/dotnet/corefx/commit/3ed51f91220858f5f8f84579e184bda406ff41b8

Updating corefx to use new roslyn compiler (dotnet/corefx#24076)

* Updating corefx to use new roslyn compiler

* Updating to new version of the compiler and use the switch so tests pass on desktop

* Fix System.Reflection.Metadata tests

Commit migrated from https://github.com/dotnet/corefx/commit/fc4b1adb7f06687aa15f0416d83d2c27a0abf8dd

Remove System.Drawing.Common from the netfx compat package (temporary).

Commit migrated from https://github.com/dotnet/corefx/commit/f6b0fbd09b8a6dc312e55644a1353cea0fb2936d

Data-annotations length fix (dotnet/corefx#24101)

* Updated in MinLengthAttribute and MaxLengthAttribute to support ICollection<T>

* Added tests

* Fixed typo

* Trying to address two failing checks:
- Linux x64 Release Build
- UWP CoreCLR x64 Debug Build

* Implemented changes requested in review
- Extracted Count checking to an external helper to obey DRY
- Removed dependency of ICollection<T> and changed to simple reflection Count property lookup

* Added requested tests

* Added catch for MissingMetadataException.

* Extracted code from try-catch.

* Added comment as requested.

* Typo correction

Commit migrated from https://github.com/dotnet/corefx/commit/b4daeabcd906283d2845063bc681ca4fa69492e8

Merge pull request dotnet/corefx#24123 from mellinoe/system.drawing-fix-osx-loading

Fix libgdiplus function loading on OSX.

Commit migrated from https://github.com/dotnet/corefx/commit/bafbafde192e2cce70f11d679f2e39c614db0b89

Prevent ServiceControllerTests from dispose when already disposed (dotnet/corefx#24042)

* Disable ServiceProcessTest that has been failing on CI and official builds

* Prevent dispose from been called when already disposed

* Add logging to repro if RemoveService is been called twice on the same ServiceController

Commit migrated from https://github.com/dotnet/corefx/commit/c017ae3ee27605a509f4fec3560998c8754180e0

Fix libgdiplus function loading on OSX.

Commit migrated from https://github.com/dotnet/corefx/commit/bc9a9d7ed76053c9b7a5ffad6707002ff7a815db

Merge pull request dotnet/corefx#23840 from niustephanie/guidtests

Expose and add tests for span-based Guid methods

Commit migrated from https://github.com/dotnet/corefx/commit/f54d710a0b3d1577d6455c4058862acfaff65152

Wrap exceptions from ManagedHandler's server validation callback (dotnet/corefx#24111)

To match other handlers' behaviors.

Commit migrated from https://github.com/dotnet/corefx/commit/e0b912e37439118651ae12e5685b0ef7efd8f1fd

dotnet/corefx#24112 Replaced documentation summary of TryPop with text similar to TryDequeue. (dotnet/corefx#24113)

Commit migrated from https://github.com/dotnet/corefx/commit/b17c1d20b1176a55fc27fbaa1b4e8f953f3dc377

Address remaining PR feedback

Commit migrated from https://github.com/dotnet/corefx/commit/43ee827db726f401ee9c76a9c3cf2ce406934349

Expose and add tests for Guid.ctor(Span)/TryWriteBytes/TryFormat

Commit migrated from https://github.com/dotnet/corefx/commit/1c7b5536bf24e1f315ab2e8dd756828ead41c6e2

Disable NegotiateStreamTest fixture for distros without working Kerberos (dotnet/corefx#24098)

Disable NegotiateStreamTest fixture entirely because setup-kdc.sh is broken on some distros

Commit migrated from https://github.com/dotnet/corefx/commit/99bffa97b96c99d4744b4a13b5bc1cbd3eb8896a

Ensure ProcessModule for main executable is first in modules list (dotnet/corefx#24106)

Commit migrated from https://github.com/dotnet/corefx/commit/382c6835d56d72a3a63aaf8cd42784dd3ddb2dc3

Wrap cert callback leaked exceptions in WinHttpHandler (dotnet/corefx#24107)

Similar to the fix done for CurlHandler (dotnet/corefx#21938), fix WinHttpHandler so
that leaked exceptions from the user-provided certificate callback are
properly wrapped.

The ManagedHandler still needs to be fixed since it is not wrapping
properly.

Contributes to dotnet/corefx#21904

Commit migrated from https://github.com/dotnet/corefx/commit/ca5d83ec2855afa7ce4f60d9c5b0dd46e1cb2faf

Add the target to copy the serializer to publish folder. (dotnet/corefx#24096)

Commit migrated from https://github.com/dotnet/corefx/commit/f472d663a6e9829483543de55cf830fc13d4818b

Add warning by default in SGEN (dotnet/corefx#24054)

* Output warning by default if run the tool directly without /quiet parameter.

* add quiet parameter in the command.

* fix parameter error.

* Update the warning.

Commit migrated from https://github.com/dotnet/corefx/commit/b5d944782098796b404ba20356cd36e384464cbc

ConcurrentQueue 128-byte cache line (dotnet/corefx#22724)

ConcurrentQueue 128-byte cache line

Commit migrated from https://github.com/dotnet/corefx/commit/9c468a08151402a68732c784b0502437b808df9f

Add btrfs and other missing file system types (dotnet/corefx#24102)

* Uppercase

* Add more filesystems from stat.c. Change to stat names where possible

* Add some more local friendly names

* Add some more remote file types from stat.c

* Add entry to switch present in enum

* Build errors

* Remove Fixed entries that should be RAM

* comment

* Change case of 0X to 0x

* Move cramfs to Fixed

Commit migrated from https://github.com/dotnet/corefx/commit/f77a66355ca596276b5905575a6976e925ef046d

Fix RHEL6 linux/in.h file detection (dotnet/corefx#24100)

On RHEL6, the build got broken by my recent fix of the in_pktinfo /
ip_mreqn detection fix. The reason is that on that platform, linux/in.h
cannot be included on its own, the sys/socket.h needs to be included
before that to provide definitions of some structures. In fact, Linux
doc states that the sys/socket.h should be included before the
linux/in.h. So I am fixing that by adding that include to the detection
code.

Commit migrated from https://github.com/dotnet/corefx/commit/d3dbd54336a1766031be18c1838c71119b54ae4b

Increase some networking test timeouts (dotnet/corefx#24099)

* Increase timeouts to attempt to harden against dotnet/corefx#18907

* Increase Sockets passing test timeout

Commit migrated from https://github.com/dotnet/corefx/commit/1e50513872aa684abf9701f58ab036970343019d

Remove an assertion from PrintDocumentTests.cs. (dotnet/corefx#24097)

Commit migrated from https://github.com/dotnet/corefx/commit/20bcbcc5392cdadcbf23b1e114ad109ca7fa186e

Add Socket.Send/Receive concurrency test (dotnet/corefx#24056)

Help validate that on Unix we're able to invoke Send/Receive multiple times to run concurrently on the same socket instance.  We already have similar tests for Send/ReceiveAsync, so this just adds one for the synchronous Send/Receive.

Commit migrated from https://github.com/dotnet/corefx/commit/e48025a81b9a53e8e073c718c8714c4c8e3f5625

Merge pull request dotnet/corefx#24091 from mellinoe/disable-serializer.generator-tests-arm64

Disable XmlSerializer.Generator.Tests on ARM64.

Commit migrated from https://github.com/dotnet/corefx/commit/e1f54cba4a1f0554e9eae0259b443c19e72ae7fb

Merge pull request dotnet/corefx#24088 from mellinoe/x86-nupkg

Add a NuGet package for System.Runtime.Intrinsics.X86.

Commit migrated from https://github.com/dotnet/corefx/commit/caca392f4d814104fcbe3d49853724d70dcf90b5

Include the fwlink in the warning. (dotnet/corefx#24082)

* Include the fwlink in the warning.

* use instructions

Commit migrated from https://github.com/dotnet/corefx/commit/307fc13500f8f13ee90f92bffda68a65547c1a93

Disable XmlSerializer.Generator.Tests on ARM64.

Commit migrated from https://github.com/dotnet/corefx/commit/5fed8b1b67a10333504b5f8c71b68431b0208f27

Merge pull request dotnet/corefx#24030 from hqueue/fix/issue_24029_tc_build_break

Disable building Microsoft.XmlSerializer.Generator.Tests for ARM

Commit migrated from https://github.com/dotnet/corefx/commit/37d8b88be5ce98a86aa5b17998f747cc9e2a06cf

Fixing build failure on CI happening on Centos (dotnet/corefx#24078)

* Fixing build failure on CI

fixes dotnet/corefx#24066

* applying code review comments

* changing IEnumerable to string[]

* applying code review comments

Commit migrated from https://github.com/dotnet/corefx/commit/2ba1f89c1a4a45bc5d7e2079175fd600f51f50ef

Auto-generate the itemgroup. (dotnet/corefx#24079)

Commit migrated from https://github.com/dotnet/corefx/commit/34873d5ec4187a69eaad2d2a06b40737037ebad3

Add a NuGet package for System.Runtime.Intrinsics.X86.

Commit migrated from https://github.com/dotnet/corefx/commit/bc741c6a255d51de531b8323d723ec95ea8711bf

Add copyright header from Mono to HttpUtility.cs (dotnet/corefx#24080)

Fixes dotnet/corefx#24043

Copied from Mono: https://github.com/mono/mono/blob/dotnet/corefx@0af1ea70c29a66a59765183b45d6b75fa6c3d8fa/mcs/class/System.Web/System.Web/HttpUtility.cs#L3-L30

Commit migrated from https://github.com/dotnet/corefx/commit/291cf9224cba8b75ba66b21cc435920f7b1027f4

Add help method for SGEN. (dotnet/corefx#23966)

* Add help method.

* Remove unused help information.

* Update the header.

Commit migrated from https://github.com/dotnet/corefx/commit/aa2dd571dc738373fc2e32f3098e4d0b1da4639c

Remove ContinueAsError in sgen test (dotnet/corefx#24015)

* Remove ContinueAsError

* Remove casesensitive

Commit migrated from https://github.com/dotnet/corefx/commit/29d0c87fce1480c8f1cf7ad66463590ef494015e

Generate Microsoft.XmlSerializer.Generator.props. (dotnet/corefx#24084)

Generate the props file on the fly so that the file can use the correct
reference version.
a

Commit migrated from https://github.com/dotnet/corefx/commit/17f71e0707d22f6ce936eb01ac0dad37e1be6c79

Update list of System.Net.* SMEs (dotnet/corefx#24077)

Commit migrated from https://github.com/dotnet/corefx/commit/a48e2d02d8d116a5d6c81ff46ca7cd158238c68d