Fixes dotnet/corefx#14839:
- This test is failing occasionally
- The parent task's status verification did not account for the child and parent tasks completing just before the verification


Commit migrated from https://github.com/dotnet/corefx/commit/e32c99048526e2134eb68f0caa144550cbfee4b2

- Adds a number of new tests
- Cleans up / clarifies some code
- Removes a chunk of duplicate code

Commit migrated from https://github.com/dotnet/corefx/commit/4a6cead5d3a0cdc3f0b6481ac082ad983ffd63bd

Commit migrated from https://github.com/dotnet/corefx/commit/48661a20d332cc19ae7cecaf69ab0e95a2abc50a

Commit migrated from https://github.com/dotnet/corefx/commit/63dd90b2d8ff169cb18e860073af054c54987241

System.IO.Compression Cleanup

Commit migrated from https://github.com/dotnet/corefx/commit/2f554b13fe67c8cf9b37c70a711de1ba5575638c

Replace API Set with Win32 DLL in tests

Commit migrated from https://github.com/dotnet/corefx/commit/158800db40864779aadbe2b2e6916dbc495060b6

Commit migrated from https://github.com/dotnet/corefx/commit/93d99e8c797e311059f822036e7598fe58d71e3e

* Disable build for fast span

Temporarily disable fast span within the package until JIT work is done.

* Adjusting test build file so the tests execute


Commit migrated from https://github.com/dotnet/corefx/commit/74612beb0220d2072de6340a5ec8ad1179b957cf

API Sets are not available on Windows 7, thus tests need to
import from Win32 DLL to run successfully on Windows 7.
Resolves issue dotnet/corefx#14728.


Commit migrated from https://github.com/dotnet/corefx/commit/21296d01c360e5febf4f9d7c501158cf740c604c

* Update LocalAppContext DisableCaching and XmlSchemaSet Tests


Commit migrated from https://github.com/dotnet/corefx/commit/05ae65fd6b51f865750e8d400c60511fcdbbbfb5

Commit migrated from https://github.com/dotnet/corefx/commit/878c378cbd7d6155ea7ebb60dbaa9d77cdb6b975

Fix XLinqTests.TreeManipulation outerloop failures

Commit migrated from https://github.com/dotnet/corefx/commit/4d7a01b0374408ed800ce899aaa65bdc3fc86142

Revert SslStream.WriteAsync, change SslStream to use innerStream.Read/WriteAsync

Commit migrated from https://github.com/dotnet/corefx/commit/5ccb1e47a8fe954c67026a577af99cb51166e68b

The test needed to handle the case when having encoding enabled to produce preamble bytes BOM (e.g. UTF8)
calling Encoding.GetBytes doesn’t include the BOM while the console stream will include it.
The fix is just handling the BOM when we'll have it.

Commit migrated from https://github.com/dotnet/corefx/commit/c393a1f5525775e28ecb28c13d38da0981e9dfe9

Minor cleanup throughout.


Commit migrated from https://github.com/dotnet/corefx/commit/dd2cb01b415b496b912c119311a81f6e59c0d428

Remove Debug Failures from FSW Win32

Commit migrated from https://github.com/dotnet/corefx/commit/7834f6b59bbcb583f09bb1a8054390c4d3ae10fc

Make buildproj package generation ARM64 specific

Commit migrated from https://github.com/dotnet/corefx/commit/63fefc893aa7d6e99b11ce10f47713466a2bd498

Remove an unused using from Vector.tt/cs

Commit migrated from https://github.com/dotnet/corefx/commit/973bcfd027028d659f6ef704cc25233ecdc92e47

Commit migrated from https://github.com/dotnet/corefx/commit/fd19a22b6157e0dda313531b062c9336698f0615

The packages.zip generation in build.proj is only used in the ARM64 CI, but it isn't Platform specific. This is causing failures elsewhere.


Commit migrated from https://github.com/dotnet/corefx/commit/3734c44ddfa10ca157c5c11d4021b4760f2dcd9b

Commit migrated from https://github.com/dotnet/corefx/commit/71e86028f2e5cb6a9381b9b51e553b3c1774dc28

There are some Debug.Fail calls in the win32 FileSystemWatcher that can be hit in normal operation sometimes. We've already established a behavior for these scenarios (use null as the old/new names when they're not available), so we shouldn't be debug asserting that they're not possible.


Commit migrated from https://github.com/dotnet/corefx/commit/f774ff39b164b33fb09c0f0a84497245608a5d90

Update CoreClr to beta-24904-03 (master)

Commit migrated from https://github.com/dotnet/corefx/commit/1b6d2c37efc6246ffe270910b6e8a99e8658cb16

Commit migrated from https://github.com/dotnet/corefx/commit/a2bb9df735446fc5c36d952a27ca455c05eaabdb

Disable several XLinq tests failing all outerloop runs

Commit migrated from https://github.com/dotnet/corefx/commit/e22a66d1e00af56f8abb1696d74914abe8d28d1e

* Fix XMLdoc for Vector<T> Inequality.

The != operator claims that it "Returns a value that indicates whether any single pair of elements in the specified vectors is equal." which is a copy-paste error from Vector.EqualsAny<T>().

* Moved changes to tt file and changed text.


Commit migrated from https://github.com/dotnet/corefx/commit/fdc601af2749324a7565d7b5fb614de6350cb10c

Commit migrated from https://github.com/dotnet/corefx/commit/e75b6ec7157320f8877b752e7c102fd56d6adc9f

Commit migrated from https://github.com/dotnet/corefx/commit/d2e9a03bab403acaca2bd205349ba48723b7dcd3

Update CoreClr, CoreFx, ProjectNTfs to beta-24904-02, beta-24904-01, beta-24904-00, respectively (master)

Commit migrated from https://github.com/dotnet/corefx/commit/7608aae7298173e73d0cdac95268f62f429e77ef

In .NET Core 1.x, SslStream's usage of Begin/EndRead/Write was actually using extension methods that just used TaskToApm.Begin/End with Read/WriteAsync.  When the base Stream's Begin/EndRead/Write methods were added back, SslStream's usage of these methods started binding to the base methods, such that it was no longer using the inner stream's Read/WriteAsync.

This change explicitly switches all of those calls (for both SslStream and NegotiateStream) to use Read/WriteAsync.  A better solution is to actually add SslStream.Read/WriteAsync overrides that use async/await and tasks all the way down, rather than going back and forth between Tasks and APM, but that is a more complicated work item.  This addressesses the immediate need (problems related to deadlocks on SslStream when read and writes are issued to run concurrently on the same stream) and can be undone or augmented subsequently when a better solution is available.

This is at least as good performance-wise as what we had in .NET Core 1.x, and in some cases is a bit better, as we can avoid creating the IAsyncResult wrapper in some cases if the returned task is already completed.


Commit migrated from https://github.com/dotnet/corefx/commit/856fb3dae9be9f30fc74aa152c64ff28bfbf6041

Commit migrated from https://github.com/dotnet/corefx/commit/1988b496ab2434210440526c832354773d653ddf

[System.IO.Compression] Remove unused (duplicate) CompressionMode.cs

Commit migrated from https://github.com/dotnet/corefx/commit/aa518043acc2cee8cf94df9808d661597369cb5d

This reverts commit dotnet/corefx@6031c507a0ea912ede85ca9fc3b8afc9a0fe70f0.


Commit migrated from https://github.com/dotnet/corefx/commit/64e0db74f9ba3fecb8e95f4149298e0355e065ce

Commit migrated from https://github.com/dotnet/corefx/commit/46dd5eea33cfeacace24c572eb525c0dc2179c8f

Commit migrated from https://github.com/dotnet/corefx/commit/81832da776d1502b0a68219cba6b8cbaf9399ed6

The changes here are just a clean up for previous changes introduced the Console OS Encoding

Commit migrated from https://github.com/dotnet/corefx/commit/53976999c0fb2c413ad71238c1e3da5fb434b118

* Fill some testing gaps related to array expressions.

* Test TypeAs expressions between nullables.

* Test fault and finally after many such blocks

(catch regressions in a non-optimised path hit in this case).


Commit migrated from https://github.com/dotnet/corefx/commit/5390a66eb8be20863535c5c3378d880e95ccee34

Fix race condition in SslStream_StreamToStream_WriteAsync_ReadAsync_Pending_Success (dotnet/corefx#14830)

* Fix race condition in SslStream_StreamToStream_WriteAsync_ReadAsync_Pending_Success.

* Address PR feedback.


Commit migrated from https://github.com/dotnet/corefx/commit/c8f66779e3ce3fa632a16d02bee286fa081214d3

Support System.Reflection.Emit.ILGeneration tests on the full .NET Framework

Commit migrated from https://github.com/dotnet/corefx/commit/4b039b4dc2230a9017ae21680f4b3752d5bd077a

* Enable HttpListener tests on Unix.

* Remove duplicate resource strings.

* Rename Unix impl to Managed, and fix license headers.

* Use HttpKnownHeaderNames for Managed http header strings.

* Return null instead of a random UriReferrer on Managed HttpListener.


Commit migrated from https://github.com/dotnet/corefx/commit/478a76963d27ac091d6735d5ee63594ff4e309af