Revert rL366946 : [Remarks] Add support for serializing metadata for every remark streamer

This allows every serializer format to implement metaSerializer() and
return the corresponding meta serializer.
........
Fix windows build bots
http://lab.llvm.org:8011/builders/llvm-clang-x86_64-win-fast
http://lab.llvm.org:8011/builders/llvm-clang-lld-x86_64-scei-ps4-windows10pro-fast
http://lab.llvm.org:8011/builders/llvm-clang-x86_64-expensive-checks-win

llvm-svn: 367004