Merge pull request #8429 from markdroth/service_config2

src/core/ext/client_channel/client_channel.c

src/core/ext/client_channel/method_config.c

src/core/ext/client_channel/method_config.h

src/core/lib/channel/message_size_filter.c

src/core/lib/transport/mdstr_hash_table.c

src/core/lib/transport/mdstr_hash_table.h