Add symbol packages for coreclr runtime.

Depends on the new buildtools symbol support.

Update build tools version containing the new symbol file support.

Commit migrated from https://github.com/dotnet/coreclr/commit/1800e5f71da458298e25b52ce35e0c6ae5976fcc

Merge remote-tracking branch 'upstream/master'

Commit migrated from https://github.com/dotnet/coreclr/commit/bfbde8d29cf245a0bf1eb027367851ad84aafa61

Merge pull request dotnet/coreclr#4269 from adiaaida/longSub

Add support for x86 long subtract operator

Commit migrated from https://github.com/dotnet/coreclr/commit/dadc7388d0a323ef14eff8ffec74724577338c45

Merge pull request dotnet/coreclr#4206 from BruceForstall/RyujitX86

Clean up JIT build rules

Commit migrated from https://github.com/dotnet/coreclr/commit/fc2f411a11709ffd3db9134a2e49c7ab1239c1c5

Merge pull request dotnet/coreclr#4221 from BruceForstall/Cleanup1

Cleanup: be consistent about compCalleeFPRegsSavedMask #ifdefs

Commit migrated from https://github.com/dotnet/coreclr/commit/46ee199e23ef8d7bae3c3a29e98383734877ef3f

Merge pull request dotnet/coreclr#4239 from BruceForstall/Cleanup2

Cleanup: remove getFramePointerReg()

Commit migrated from https://github.com/dotnet/coreclr/commit/9971220e29584ea5a696c544f7e24140aa973999

Merge pull request dotnet/coreclr#4242 from BruceForstall/Cleanup3

Add genEstablishFramePointer() to enapsulate frame pointer creation

Commit migrated from https://github.com/dotnet/coreclr/commit/ac914bdbcf65a1e482ab5de541cb0c2d5b089855

Merge pull request dotnet/coreclr#4243 from BruceForstall/Cleanup4

Minor JIT changes

Commit migrated from https://github.com/dotnet/coreclr/commit/16b539a95181a7ce2856726f751af0edc2a55c49

Add support for x86 long subtract operator

With dotnet/coreclr#3296, we have all the support for subtracting longs on x86. Subtract
can use the same logic as addition for longs.

Fixes dotnet/coreclr#4189.

Commit migrated from https://github.com/dotnet/coreclr/commit/6b87d20fddd80250b51465cf18499bd08865af80

Merge pull request dotnet/coreclr#4240 from LLITCHEV/Issue4147

Add test for issue 4115.

Commit migrated from https://github.com/dotnet/coreclr/commit/2eb214ee49e3474ec64aad04ac673f7f18379c95

Merge pull request dotnet/coreclr#4245 from AndyAyersMS/ModelPolicy

Inliner: initial version of a model-based policy

Commit migrated from https://github.com/dotnet/coreclr/commit/926dd1fd3158dc7fc691480ea54ed9b399f91d30

Merge pull request dotnet/coreclr#3990 from myungjoo/testing/fix3856

Fix Linux-ARM Broken Stack w/ ThePreStub

Commit migrated from https://github.com/dotnet/coreclr/commit/e8c82e2c4363b58b76c036ba6db5a192f4e3d33b

Merge pull request dotnet/coreclr#4257 from jkotas/noexecstack

Pass noexecstack option to the assembler on Linux

Commit migrated from https://github.com/dotnet/coreclr/commit/96be08ac560f8529c413dc3be50b66bb7b25348e

Add a test for Issue 4147.

This checkin adds a test for Issue 4147.

Commit migrated from https://github.com/dotnet/coreclr/commit/e2637731b980a6d73c5bb244720f4a5931001727

Merge pull request dotnet/coreclr#4250 from yizhang82/nativevariant_fix

Fix GetObjectForNativeVariant test issue. It should roundtrip the actual object instead of IntPtr. Also add proper variant clean up code.

Fix dotnet/coreclr#4192.

Commit migrated from https://github.com/dotnet/coreclr/commit/ff26d6801b3ce0dec5918a5ad0d3ab90f9656e28

Pass noexecstack option to the assembler on Linux

Commit migrated from https://github.com/dotnet/coreclr/commit/f4b8f67019928536dc1a98caea5e17221824376b

Merge pull request dotnet/coreclr#4253 from jamesqo/faulty-trues

Fix a couple of erroneous assert(trues)

Commit migrated from https://github.com/dotnet/coreclr/commit/2ee084a216d42708074cb9a94b316db72c664c3f

Merge pull request dotnet/coreclr#4256 from yizhang82/chararray_fix

Change Marshal.SizeOf to sizeof to calculate buffer size because Marshal.Copy copies managed contents, while Marshal.SizeOf gives native size. Fix dotnet/coreclr#4254

Commit migrated from https://github.com/dotnet/coreclr/commit/88f55f5fe9ae57c0e173d87e7cb4c5a0c4da6d02

Change Marshal.SizeOf to sizeof because Marshal.Copy copies managed contents and does not do marshalling.

Commit migrated from https://github.com/dotnet/coreclr/commit/baf7569a45d83237bd933acfa8a8a568ca7c5e33

Merge pull request dotnet/coreclr#4249 from yizhang82/lptstr_fix

Fix LPTSTRTest failure - it has a incorrect constant probably due to bad merge. Fix dotnet/coreclr#4197

Commit migrated from https://github.com/dotnet/coreclr/commit/c835bdc46cd2c39ae0666af56b4191b4090610b7

Fix GetObjectForNativeVariant test issue. It should roundtrip the actual object instead of IntPtr. Also add proper variant clean up code.

NOTE that I had to keep Marshal.IUnknownForObject call to force COM initialization.

Commit migrated from https://github.com/dotnet/coreclr/commit/a1ffff4a8e305c1e06548aee8cdc43a091fab3ac

Merge remote-tracking branch 'upstream/master'

Commit migrated from https://github.com/dotnet/coreclr/commit/d92e5fce53eb63541cf14f2d40486a1559d4e6ca

Fix LPTSTRTest failure - it has a incorrect constant probably due to bad porting. Also remove StringMarshal tests from issues.targets

Commit migrated from https://github.com/dotnet/coreclr/commit/6f3ed699dd21347a953dff5d2607cc620258f141

Fix a couple of erroneous assert(trues)

Commit migrated from https://github.com/dotnet/coreclr/commit/c92467665a8519fa0c5d9be7b7ec5d760b37d38b

Merge pull request dotnet/coreclr#4248 from dotnet/revert-4199-struct16-abi

Revert "ARM64 Work Item 3817, 3524 - Struct16 decomposition"

Commit migrated from https://github.com/dotnet/coreclr/commit/32b2d2c0a5900ff85b941b29a08b05ff08d7f44b

Revert "ARM64 Work Item 3817, 3524 - Struct16 decomposition"

Commit migrated from https://github.com/dotnet/coreclr/commit/6b4320b16364eb59c1164c9a5b90d3e3046da72f

Merge pull request dotnet/coreclr#4162 from ramarag/ResolveWorkerChainLookupAsmStub

[Arm64]:Fixing the Logic of ResolveWorkerChainLookupAsmStub for VSD

Commit migrated from https://github.com/dotnet/coreclr/commit/d0079786f342e2bd2ccc66c04815f80fee58111d

Merge pull request dotnet/coreclr#4202 from MichalStrehovsky/applicationException

Remove usage of ApplicationException in tests

Commit migrated from https://github.com/dotnet/coreclr/commit/749bec55fbb3eab0cf8abc6123e377478ceafe8a

[Arm64]:Fixing the Logic of ResolveWorkerChainLookupAsmStub

Commit migrated from https://github.com/dotnet/coreclr/commit/df01dac9db7757bc3bee4c2c8a50157a3e7da097

Inliner: initial version of a model-based policy

Add a model-based size predictor to the `DiscretionaryPolicy` and
dump its data along with observations. This can be used to assess
the performance of the model. Currently using a linear model that
can explain about 55% of the variability in code size impact for
mscorlib. Whether this holds up for other situations is still to
be determined.

Create a `ModelPolicy` that relies on this code size model to make
inlining decisions. This is very much a work in progress as the code
size models are still not well vetted and there is no real code
quality model yet.

Commit migrated from https://github.com/dotnet/coreclr/commit/56b4feb0e404dc0b5ef01618b090f89a388ba3be

Merge pull request dotnet/coreclr#4207 from swgillespie/437657

Remove a test that doesn't provide much value, fails in parallel test…

Commit migrated from https://github.com/dotnet/coreclr/commit/643fc4af4d30730909d6fbcfba71df8c71ee4ab3

Merge pull request dotnet/coreclr#4199 from briansull/struct16-abi

ARM64 Work Item 3817, 3524 - Struct16 decomposition

Commit migrated from https://github.com/dotnet/coreclr/commit/a09b8aac05c53a656614d6f3e0425d8be7f1e873

Minor JIT changes

Add a useful assert about SP to FP offsets.

Add "const" to a few member functions.

Commit migrated from https://github.com/dotnet/coreclr/commit/669fdc0c3df5ba3a7c155952f110926f2f17b837

Add genEstablishFramePointer() to enapsulate frame pointer creation

Commit migrated from https://github.com/dotnet/coreclr/commit/2bded17025299f91787e150baa1791967ab4f597

Cleanup: replace getFramePointerReg() with preexisting genFramePointerReg()

Commit migrated from https://github.com/dotnet/coreclr/commit/63efa21ec870e105ae2928dc2ecb0284152a8f17

Cleanup: be consistent about compCalleeFPRegsSavedMask #ifdefs

Commit migrated from https://github.com/dotnet/coreclr/commit/b19a9c06b1613b5f6f7f0c31b643e4d8f6fbe624

Merge remote-tracking branch 'upstream/master'

Commit migrated from https://github.com/dotnet/coreclr/commit/61a3365ba54b014f0b51b70814f83ef4587fecea

Merge pull request dotnet/coreclr#4205 from mikem8361/sosfx2

Better sos message for runtime not initialized

Commit migrated from https://github.com/dotnet/coreclr/commit/ac2ffdd6c7dd23043c111e010298713c12aecbe4

Merge remote-tracking branch 'upstream/master'

Commit migrated from https://github.com/dotnet/coreclr/commit/017b06da5c52e29a249943f0736c854c9b2f97ba

Merge pull request dotnet/coreclr#4163 from pgavlin/GCInfoQSort

Replace CQuickSort with qsort in GC info encoders.

Commit migrated from https://github.com/dotnet/coreclr/commit/96580e43ebec236e711373da7397aa92efe99d77

ARM64 Work Item 3817, 3524 - Struct16 decomposition

Changes to support passing of MultiReg structs using GT_LISTs
Optional support for  struct promotion for multireg structs:
To enable set  FEATURE_MULTIREG_STRUCT_PROMOTE to 1
Morphs the 16-byte structs at the end of fgMorphArgs
Careful refactoring to avoid changes to UNIX_AMD64 code
Covers all of the 16-byte struct expansion cases in fgMorph
Added function header comments
Passing the tests for Arm64
No AsmDiffs for non-Arm64 targets.
Codegen uses Contained nodes for PUTARG_STK 16-byte stack args
Created a genPutArgStk method for Arm64

Commit migrated from https://github.com/dotnet/coreclr/commit/624873164f05996ab04053a37b108a2a53114b04

Remove a test that doesn't provide much value, fails in parallel test environments, and p/invokes to kernel32.dll

Commit migrated from https://github.com/dotnet/coreclr/commit/232c6c347a95bb15e9e2c6311b5343cbbc65a473

Merge pull request dotnet/coreclr#4198 from dotnet-bot/from-tfs

Merge changes from TFS

Commit migrated from https://github.com/dotnet/coreclr/commit/de0c5bc7f717b741d1f979903146507d1c16702c

Merge pull request dotnet/coreclr#4203 from mmitche/remove-unused

Remove unecessary jobs

Commit migrated from https://github.com/dotnet/coreclr/commit/0cab5911cebf32982a1e0599e119f4422477d763

Better sos message for runtime not initialized

Also fixed the corerun sos command checked build problem.

Commit migrated from https://github.com/dotnet/coreclr/commit/b9c4214079929094d36fa9afdf8b9d34b6eeae6c

Remove unecessary jobs

The jobs that involve multiple build stages (like most things xplat) always use the native bits from the default scenario.  Remove builds that are unused

Commit migrated from https://github.com/dotnet/coreclr/commit/7aef1c0471c2a3c1f81e0bb0318ec62f63651f0a

Clean up JIT build rules

Add SIMD files to x86 build (they aren't used, yet).

Separate out the LEGACY_BACKEND files, to be explicit about them.

Make protojit and standalone build rules more similar.

Commit migrated from https://github.com/dotnet/coreclr/commit/d096d92f5fcf7c9b359ef026bdf912843ee0cbd2

Remove usage of ApplicationException in tests

ApplicationException is not in the .NET Core profile. Most of these
tests only use it to crash the test with an unhandled exception and it
doesn't matter what exception type it is.

Commit migrated from https://github.com/dotnet/coreclr/commit/d037a9e83ff26a47a4a2f38ef9ef4c184b219262

Add missing .gitmirrorall file

[tfs-changeset: 1594511]

Commit migrated from https://github.com/dotnet/coreclr/commit/3ba29c077a569e560a9c4df617e2976b841116c7

Merge branch 'botaberg-port_interop_tests'

Commit migrated from https://github.com/dotnet/coreclr/commit/4ee08c7f344a49e27dfece22cf0ff5159158e22b

Merge branch 'port_interop_tests' of https://github.com/botaberg/coreclr into botaberg-port_interop_tests

Commit migrated from https://github.com/dotnet/coreclr/commit/9eeaadcbcb270b9a101aaeb35a6a983da20c217b

Merge pull request dotnet/coreclr#4164 from yizhang82/lpstr_test_fix

Fix LPSTR test failure due to incorrect implementation of strncpy_s.

Commit migrated from https://github.com/dotnet/coreclr/commit/7770c88ff4f672071d6365498a8c942d0417253c

Merge pull request dotnet/coreclr#4160 from tijoytom/master

Windows specific Marshal APIs test.

Commit migrated from https://github.com/dotnet/coreclr/commit/a85c2686820fa9f79dc5b40e975dcb0e59367a52

Replace CQuickSort with qsort in GC info encoders.

This removes another utilcode dependency from the GC info encoders.

Commit migrated from https://github.com/dotnet/coreclr/commit/587f0075c60c839e5e7f44cbb4abb8007d086874

Merge pull request dotnet/coreclr#3642 from dagood/remove-hardcoded-versions

Remove hardcoded versions from runtests.proj

Commit migrated from https://github.com/dotnet/coreclr/commit/a6f4d4fff16f3def2312d2418fa6699d6cb897ba

Merge pull request dotnet/coreclr#4165 from myungjoo/trivialfix/doc1

Typo: incorrect pathname in documentation

Commit migrated from https://github.com/dotnet/coreclr/commit/af1db8b6a3ebe36cb5254e2730ec89b270d7ce5d

Typo: incorrect pathname in documentation

build-rootfs.sh is at ./cross/, not ./ .

Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Commit migrated from https://github.com/dotnet/coreclr/commit/c93ca508150196a506dd31f782c8866ab6fe3a97

Fix LPSTR test failure due to incorrect implementation of strncpy_s. It was implemented using snprintf and didn't account for the null terminator behavioral difference. Test is now passing after the fix. We should see if we can always use xplat helpers in all platforms for easier debugging.

Commit migrated from https://github.com/dotnet/coreclr/commit/78595418e12b1059e94b3b5d031da007b1be6794

Merge pull request dotnet/coreclr#4155 from MichalStrehovsky/debuggableAttribute

Remove mscorlib 1.x strong references from tests

Commit migrated from https://github.com/dotnet/coreclr/commit/775933742b8cb9bd6f576c244a7b44f788e462e8

Merge pull request dotnet/coreclr#4161 from yizhang82/remove-marshal

Remove Marshal.Read/Write (AsAny object) overload from CoreCLR.

Commit migrated from https://github.com/dotnet/coreclr/commit/b10b8e8245e0b3c7a017a8237e5549b0a7791a5d

Merge pull request dotnet/coreclr#4134 from MichalStrehovsky/junkAttributes

Delete junk attributes in tests

Commit migrated from https://github.com/dotnet/coreclr/commit/c0477fc597045f998adbbcc9c6717dd79c7ee26e

Remove Marshal.Read/Write (AsAny object) overload from CoreCLR. I don't expect anyone to use these overloads and it doesn't make sense to keep them. Their semantics are rather convoluted and most likely not what you might expect.

Commit migrated from https://github.com/dotnet/coreclr/commit/16f5695839f753b803149c9e012a924733a46a5b

Windows specific Marshal APIs test.

Commit migrated from https://github.com/dotnet/coreclr/commit/3293377246ff2a446b15f675aa834747db79eae0

Merge pull request dotnet/coreclr#4159 from kyulee1/update3

ARM64: Update email notification3 -- testing

Commit migrated from https://github.com/dotnet/coreclr/commit/367952fc99132d58d5b9f1d891c5edd6b0a6e7e3

ARM64: Update email notification3 -- testing

Commit migrated from https://github.com/dotnet/coreclr/commit/28070fc4d5321e1e44a4132607523bf5a3e917ea

Merge pull request dotnet/coreclr#4125 from wtgodbe/errLog

Add error logging to 4 PAL tests that fail periodically on OSX

Commit migrated from https://github.com/dotnet/coreclr/commit/9f26682695fd54f00905d21b2ae4bb6db31c1055

Merge pull request dotnet/coreclr#4149 from wtgodbe/triggerPhrases

Add documentation for CI Trigger Phrases

Commit migrated from https://github.com/dotnet/coreclr/commit/0cc126f6c4f1ff8d9316d56a0e68950a6bafa3b8

Add documentation for CI Trigger Phrases

Commit migrated from https://github.com/dotnet/coreclr/commit/6a210c6bbcb9438a47e0da0ca2103348320e2efb

Merge pull request dotnet/coreclr#4131 from dotnet/Petermarcu-patch-2

Updating Readme to point to .NET Core SDK

Commit migrated from https://github.com/dotnet/coreclr/commit/6ddf7675dce1a40c74c885012c28cf46f7b5ffae

Merge pull request dotnet/coreclr#4153 from kyulee1/update2

ARM64: Update email notification2

Commit migrated from https://github.com/dotnet/coreclr/commit/e50c72dcc80e91d9ef08940ab94135ad629fd076

ARM64: Update email notification2

Only for arm64 group (both PR/Push) -- testing.

Commit migrated from https://github.com/dotnet/coreclr/commit/28134411f660e634a79f0b2c70b392bbd987a850

Merge pull request dotnet/coreclr#4148 from AndyAyersMS/InlineOpcodeBins

Inliner: update DiscretionaryPolicy to look at opcodes and arg info

Commit migrated from https://github.com/dotnet/coreclr/commit/be8155b7594badb580932e18f05bf390e26ba59f

Remove mscorlib 1.x strong references from tests

Referencing mscorlib 1.x forces ILASM to emit a reference to the legacy
DebuggableAttribute constructor (the one that takes bools). That
constructor is not in the .NET Core profile and not all core base class
libraries will have it.

See src/ilasm/asmman.cpp#L389.

Commit migrated from https://github.com/dotnet/coreclr/commit/c3a552ce7698fe7381600eaf8d34244a8ee4b0d8

Fixing failures of CscBench, Serialization and Deserialization perf tests (dotnet/coreclr#4151)

Commit migrated from https://github.com/dotnet/coreclr/commit/36a69024d4a4e505f4eaf3a23a0df199c89eda6c

Merge pull request dotnet/coreclr#4152 from kyulee1/updateemail

ARM64: Update email notification

Commit migrated from https://github.com/dotnet/coreclr/commit/37642c399e431e0c865d0dc2a7341da2be253742

Merge pull request dotnet/coreclr#4037 from pgavlin/SimplerHashTable

Remove non-portable dependencies from SimplerHashTable.

Commit migrated from https://github.com/dotnet/coreclr/commit/7be493b6b6cbd8da386e2b526a3b3872bdd7cbbb

Inliner: update DiscretionaryPolicy to look at opcodes and arg info

Have the `DiscretionaryPolicy` do some simple opcode histogramming
to try and provide better observations for code size estimation.

Likewise, look at the types and sizes of arguments and report those.

Commit migrated from https://github.com/dotnet/coreclr/commit/95e8431a6d0d89600811dc9f59a39f5673a9df08

ARM64: Update email notification

Only sending email for Windows run when push occurs.
Skip sending email for private run (PR).

Commit migrated from https://github.com/dotnet/coreclr/commit/d5803df484f86c6ca28f0fb73c422e2d1b322d8d

Merge pull request dotnet/coreclr#4106 from janvorli/add-hosting-api-header

Add header file for the hosting API

Commit migrated from https://github.com/dotnet/coreclr/commit/672a0da39226f35341cc6f5dc6c9cb4a39765f96

Merge pull request dotnet/coreclr#4144 from kyulee1/email

ARM64: Add email notification for failing job

Commit migrated from https://github.com/dotnet/coreclr/commit/772e25741bb14f8bde6ae7720a3d9119c89a892f

Merge pull request dotnet/coreclr#4146 from mmitche/fix-trigger-phrases

Trigger phrase currently has invalid regex

Commit migrated from https://github.com/dotnet/coreclr/commit/0bfb2de57c36e5e816f311f132f5d4bcf1ec5ca8

Trigger phrase currently has invalid regex

Should be double quoted for string interpolation

Commit migrated from https://github.com/dotnet/coreclr/commit/5517ea5bdc230efad97f1912e931f18326a466f6

ARM64: Add email notification for failing job

Similar to roslyn job, added an email publisher to the job.
Fixed job title to reflect "Test" for Checked/Release case.
Refined triggered message to enable individual configuration.
So, instead of "test Windows_NT arm64" that runs all configurations,
just "test Windows_NT arm64 Checked" for instance.

Commit migrated from https://github.com/dotnet/coreclr/commit/29825554bbcbfecb76fba369cb12f77a96e83fb3

Merge pull request dotnet/coreclr#4139 from kyulee1/launcher

ARM64: Launch test build and run in parallel

Commit migrated from https://github.com/dotnet/coreclr/commit/50ea585d52cd4cf49a7ccb2df6b9dcc19437493b

Merge pull request dotnet/coreclr#4061 from jamesqo/use-roslyn

Remove UseRoslynCompiler variable from the build system

Commit migrated from https://github.com/dotnet/coreclr/commit/5e1f70cabf7e4f58c273452951fff53f1fd6981e

Merge pull request dotnet/coreclr#4136 from yizhang82/castable_fix

Re-enable ICastable test now that it is passing on Mac

Commit migrated from https://github.com/dotnet/coreclr/commit/f760168ecd5469a22b8e3a94351750f9532d2abb

Merge pull request dotnet/coreclr#4099 from ramarag/gcstackwalk

[ARM64] Fixes Updating Registers for managed frames in GC stack walks

Commit migrated from https://github.com/dotnet/coreclr/commit/083181f8e1743080893495cf1229e2f60f3d3542

ARM64: Launch test build and run in parallel

This change allows to buildtest.cmd for arm64 in separate.
Currently we build coreclr and tests for arm64 and then run tests in
sequence even though we run the pre-built test suite.
This change pushes down the test built part into the lab post script that
launches buildtests.cmd and arm64postbuild.cmd concurrently. The latter
part is mostly waiting for the results from arm64 box. So we can almost
hide the test build time which is around 30 min.

Commit migrated from https://github.com/dotnet/coreclr/commit/c8ff926bf94279e925fe25cea9412c322e767542

Merge pull request dotnet/coreclr#4137 from AndyAyersMS/RelModeILTests

Set DebugType to PdbOnly for rel-mode IL tests

Commit migrated from https://github.com/dotnet/coreclr/commit/8d11e0bf15df0833a900334d60f16deb4db6cb1e

Merge pull request dotnet/coreclr#3874 from swaroop-sridhar/CDT

Add CoreDisTools header

Commit migrated from https://github.com/dotnet/coreclr/commit/4472a2285298d932cf01a902c44f5379bc2d4338

Set DebugType to PdbOnly for rel-mode IL tests

Ensures that execution of these tests always invokes the jit's optimizer,
regardless of the build configuration.

See issue dotnet/coreclr#4124.

Commit migrated from https://github.com/dotnet/coreclr/commit/37abad16e69c4d8cd91810d0698d015b0e2845ea

Fixes Updating Registers for managed frames in stack walks

Commit migrated from https://github.com/dotnet/coreclr/commit/87434bb371ab0700241f07d6e637e16eb29fcfd8

Re-enable ICastable test now that it is passing on Mac

Commit migrated from https://github.com/dotnet/coreclr/commit/550b18d2c655ce328ce60c49baaf03550add73a4

Delete junk attributes in tests

There is no such thing as
`Microsoft.VisualBasic.Globals$StandardModuleAttribute` and
`System.Security.SecurityRulesAttribute` in mscorlib. Presence of these
unresolvable references just trips up static compilers.

Commit migrated from https://github.com/dotnet/coreclr/commit/29097ca2a2cab90822912d07f3f8ae7a1e2416af

Merge pull request dotnet/coreclr#4111 from kyulee1/customlauncher

Restore CustomLauncher to Test Population

Commit migrated from https://github.com/dotnet/coreclr/commit/7f95d79740d5f5b13d6a0df1b94654e622053a5f

Merge pull request dotnet/coreclr#4119 from tarekgh/FixAsyncCurrentCulture

 Make current culture travel with async operations on Linux

Commit migrated from https://github.com/dotnet/coreclr/commit/e609a4f2272412f0ad3ce1f8e22c2b4d0740388f

Add error logging to 4 PAL tests that fail periodically on OSX

Commit migrated from https://github.com/dotnet/coreclr/commit/c126c3e80835a9c4e113504684085864b91b517b

Merge pull request dotnet/coreclr#4086 from swgillespie/gc-env-vars

Fix an issue where COREHOST_SERVER_GC and COREHOST_CONCURRENT_GC were…

Commit migrated from https://github.com/dotnet/coreclr/commit/e3ad4b489429edd6d7f8315e0bc218c32bf6315f

Merge pull request dotnet/coreclr#4120 from joperezr/FixInternalBuild

Fix Internal builds where ToolsDir doesn't exist

Commit migrated from https://github.com/dotnet/coreclr/commit/1e6c5975c331e438656c67a8d772044aa9371d31

Fix Internal builds where ToolsDir doesn't exist

Commit migrated from https://github.com/dotnet/coreclr/commit/3afdd0498db2d9bbfbf28081eaeb7da922a35746