Fix trim warnings in 'WindowsRuntimeStreamExtensions'

Author: Sergio0694

src/cswinrt/strings/additions/Windows.Storage.Streams/WindowsRuntimeBuffer.cs

@@ -81,7 +81,7 @@ private static unsafe void EnsureHasMarshalProxy()
             {
                 IntPtr proxyPtr = default;
                 int hr = RoGetBufferMarshaler(&proxyPtr);
-                IMarshal proxy = new ABI.Com.IMarshal(ObjectReference<ABI.Com.IMarshal.Vftbl>.Attach(ref proxyPtr));
+                IMarshal proxy = new ABI.Com.IMarshal(ObjectReference<ABI.Com.IMarshal.Vftbl>.Attach(ref proxyPtr, global::WinRT.Interop.IIDs.IID_IMarshal));
                 t_winRtMarshalProxy = proxy;
 
                 if (hr != 0)

src/cswinrt/strings/additions/Windows.Storage.Streams/WindowsRuntimeStreamExtensions.cs

@@ -7,6 +7,9 @@ namespace System.IO
 {
     using System.ComponentModel;
     using System.Diagnostics;
+#if NET
+    using System.Diagnostics.CodeAnalysis;
+#endif
     using System.IO;
     using System.Runtime.CompilerServices;
     using System.Runtime.InteropServices;
@@ -42,10 +45,13 @@ private static readonly ConditionalWeakTable<Stream, NetFxToWinRtStreamAdapter>
         #region Helpers
 
 #if DEBUG
-        private static void AssertMapContains<TKey, TValue>(ConditionalWeakTable<TKey, TValue> map, TKey key, TValue value,
-                                                            bool valueMayBeWrappedInBufferedStream)
-                                                                                                where TKey : class
-                                                                                                where TValue : class
+        private static void AssertMapContains<TKey, [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicParameterlessConstructor)] TValue>(
+            ConditionalWeakTable<TKey, TValue> map,
+            TKey key,
+            TValue value,
+            bool valueMayBeWrappedInBufferedStream)
+            where TKey : class
+            where TValue : class
         {
             TValue valueInMap;