Add channel arg for max send message size and add message size filter.
diff --git a/grpc.gemspec b/grpc.gemspec
index 9c82db8..c69988f 100755
--- a/grpc.gemspec
+++ b/grpc.gemspec
@@ -180,6 +180,7 @@
   s.files += %w( src/core/lib/channel/handshaker.h )
   s.files += %w( src/core/lib/channel/http_client_filter.h )
   s.files += %w( src/core/lib/channel/http_server_filter.h )
+  s.files += %w( src/core/lib/channel/message_size_filter.h )
   s.files += %w( src/core/lib/compression/algorithm_metadata.h )
   s.files += %w( src/core/lib/compression/message_compress.h )
   s.files += %w( src/core/lib/debug/trace.h )
@@ -339,6 +340,7 @@
   s.files += %w( src/core/lib/channel/handshaker.c )
   s.files += %w( src/core/lib/channel/http_client_filter.c )
   s.files += %w( src/core/lib/channel/http_server_filter.c )
+  s.files += %w( src/core/lib/channel/message_size_filter.c )
   s.files += %w( src/core/lib/compression/compression.c )
   s.files += %w( src/core/lib/compression/message_compress.c )
   s.files += %w( src/core/lib/debug/trace.c )