Improve coded_stream.h handling on MSVC.  Avoid a bogus runtime check and enable little-endian optimization.  Based on patch from Nathan McDaniel.
Improve coded_stream.h handling on MSVC.  Avoid a bogus runtime check and enable little-endian optimization.  Based on patch from Nathan McDaniel.

malthe/google-protobuf,malthe/google-protobuf,malthe/google-protobuf,malthe/google-protobuf,malthe/google-protobuf