#237 Make shared CLR code internal

src/Microsoft.Net.Http.Server/Overlapped/PreAllocatedOverlapped.cs

@@ -2,7 +2,7 @@
 using System;
 namespace System.Threading
 {
-    public sealed class PreAllocatedOverlapped : IDisposable, IDeferredDisposable
+    internal sealed class PreAllocatedOverlapped : IDisposable, IDeferredDisposable
     {
         internal readonly ThreadPoolBoundHandleOverlapped _overlapped;
         private DeferredDisposableLifetime<PreAllocatedOverlapped> _lifetime;

src/Microsoft.Net.Http.Server/Overlapped/ThreadPoolBoundHandle.cs

@@ -3,7 +3,7 @@ using System;
 using System.Runtime.InteropServices;
 namespace System.Threading
 {
-    public sealed class ThreadPoolBoundHandle : IDisposable
+    internal sealed class ThreadPoolBoundHandle : IDisposable
     {
         private readonly SafeHandle _handle;
         private bool _isDisposed;