Using mscorlib shim as default resolving assembly for BinaryFormatter serialization instead of System.Private.Corelib (#20879)

* Using mscorlib shim as default resolving assembly instead of System.Private.Corelib

* Increasing serialization perf

* Doing string comparison on both mscorlib and S.P.C

Author: ViktorHofer

src/System.Runtime.Serialization.Formatters/src/System/Runtime/Serialization/FormatterServices.cs

@@ -322,7 +322,14 @@ internal static string GetClrAssemblyName(Type type, out bool hasTypeForwardedFr
                 throw new ArgumentNullException(nameof(type));
             }
 
-            foreach (Attribute first in type.GetCustomAttributes(typeof(TypeForwardedFromAttribute), false))
+            // Special case types like arrays            
+            Type attributedType = type;
+            while (attributedType.HasElementType)
+            {
+                attributedType = attributedType.GetElementType();
+            }
+
+            foreach (Attribute first in attributedType.GetCustomAttributes(typeof(TypeForwardedFromAttribute), false))
             {
                 hasTypeForwardedFrom = true;
                 return ((TypeForwardedFromAttribute)first).AssemblyFullName;

src/System.Runtime.Serialization.Formatters/src/System/Runtime/Serialization/Formatters/Binary/BinaryObjectWriter.cs

@@ -984,7 +984,7 @@ private long GetAssemblyId(WriteObjectInfo objectInfo)
             {
                 assemId = 0;
             }
-            else if (assemblyString.Equals(Converter.s_urtAssemblyString))
+            else if (assemblyString.Equals(Converter.s_urtAssemblyString) || assemblyString.Equals(Converter.s_urtAlternativeAssemblyString))
             {
                 // Urt type is an assemId of 0. No assemblyString needs
                 // to be sent 

src/System.Runtime.Serialization.Formatters/src/System/Runtime/Serialization/Formatters/Binary/BinaryTypeConverter.cs

@@ -57,7 +57,7 @@ internal static BinaryTypeEnum GetBinaryTypeInfo(Type type, WriteObjectInfo obje
                             typeInformation = objectInfo.GetTypeFullName();
                         }
 
-                        if (assembly.Equals(Converter.s_urtAssemblyString))
+                        if (assembly.Equals(Converter.s_urtAssemblyString) || assembly.Equals(Converter.s_urtAlternativeAssemblyString))
                         {
                             binaryTypeEnum = BinaryTypeEnum.ObjectUrt;
                             assemId = 0;

src/System.Runtime.Serialization.Formatters/src/System/Runtime/Serialization/Formatters/Binary/Converter.cs

@@ -30,9 +30,17 @@ internal static class Converter
         internal static readonly Type s_typeofUInt64 = typeof(ulong);
         internal static readonly Type s_typeofObject = typeof(object);
         internal static readonly Type s_typeofSystemVoid = typeof(void);
-        internal static readonly Assembly s_urtAssembly = s_typeofString.Assembly;
+
+        // In netfx the default assembly is mscorlib.dll --> typeof(string).Assembly.
+        // In Core type string lives in System.Private.Corelib.dll which doesn't 
+        // contain all the types which are living in mscorlib in netfx. Therefore we
+        // use our mscorlib facade which also contains manual type forwards for deserialization.
+        internal static readonly Assembly s_urtAssembly = Assembly.Load("mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089");
         internal static readonly string s_urtAssemblyString = s_urtAssembly.FullName;
 
+        internal static readonly Assembly s_urtAlternativeAssembly = s_typeofString.Assembly;
+        internal static readonly string s_urtAlternativeAssemblyString = s_urtAlternativeAssembly.FullName;
+
         // Arrays
         internal static readonly Type s_typeofTypeArray = typeof(Type[]);
         internal static readonly Type s_typeofObjectArray = typeof(object[]);