Move WaitHandle to shared CoreLib (dotnet/coreclr#22634)

* Move part of WaitHandle to shared CoreLib

* Bring back OpenExistingResult to fix build

* Move reminder of WaitHandle to shared, implement SynchronizationContext logic in managed code, handle SafeHandle referencing in managed code

* Update with changes neeeded for CoreRT

* Span -> ReadOnlySpan

* Remove dead code

* Fix SafeHandle error handling

* Avoid double check on input values in WaitHandle.WaitOne overloads

* Make OpenExistingResult private protected instead of internal

* Make WaitHandle._waitHandle private

* Code style fixes

* Remove unnecessary GC.KeepAlive

* Move ERROR_TOO_MANY_POSTS exception handling to CoreCLR specific code

* Add cache for wait arrays to match previous CoreRT behavior and reduce GC pressure, change unmanaged code to allocate small array on stack

* Address PR feedback

* Reduce allocations/copying by moving stack allocation to managed code

* Address PR feedback

* Minor code reshuffle

* Move thread local access close to each other

* Address code style feedback

* Add const to Wait* constants

Signed-off-by: dotnet-bot <dotnet-bot@microsoft.com>

src/Common/src/CoreLib/System.Private.CoreLib.Shared.projitems

@@ -840,6 +840,7 @@
     <Compile Include="$(MSBuildThisFileDirectory)System\Threading\Timeout.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Threading\TimeoutHelper.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Threading\Timer.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)System\Threading\WaitHandle.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Threading\WaitHandleCannotBeOpenedException.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\ThreadStaticAttribute.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\ThrowHelper.cs" />

src/Common/src/CoreLib/System/Threading/EventWaitHandle.Windows.cs

@@ -76,15 +76,15 @@ private static OpenExistingResult OpenExistingWorker(string name, out EventWaitH
 
         public bool Reset()
         {
-            bool res = Interop.Kernel32.ResetEvent(_waitHandle);
+            bool res = Interop.Kernel32.ResetEvent(SafeWaitHandle);
             if (!res)
                 throw Win32Marshal.GetExceptionForLastWin32Error();
             return res;
         }
 
         public bool Set()
         {
-            bool res = Interop.Kernel32.SetEvent(_waitHandle);
+            bool res = Interop.Kernel32.SetEvent(SafeWaitHandle);
             if (!res)
                 throw Win32Marshal.GetExceptionForLastWin32Error();
             return res;

src/Common/src/CoreLib/System/Threading/Mutex.Windows.cs

@@ -90,7 +90,7 @@ private static OpenExistingResult OpenExistingWorker(string name, out Mutex resu
         // in a Mutex's ACL is MUTEX_ALL_ACCESS (0x1F0001).
         public void ReleaseMutex()
         {
-            if (!Interop.Kernel32.ReleaseMutex(_waitHandle))
+            if (!Interop.Kernel32.ReleaseMutex(SafeWaitHandle))
             {
                 throw new ApplicationException(SR.Arg_SynchronizationLockException);
             }