Checkpoint aligned marshalling work
Eliminate some uses of Function.bind since it impairs performance dramatically in v8 and spidermonkey.
Size the marshalling scratch buffer on the fly to ensure it's always big enough
Use >> or | instead of >>> in some pointer code since Spidermonkey has historical issues with >>>.
Use encodings in BinaryReader.ReadChars and BinaryReader.ReadString
Use WeakMaps if available for Object.GetHashCode
Tweak copy constructor codegen
Force Rectangle and Point data members to int32 for better performance
More type hints in XNA classes/structs
Stop using property accessors in SpriteBatch.Draw
Fix boolean instance fields defaulting to 0 instead of false