Merge remote-tracking branch 'upstream/master' into service_config_json

BUILD

CMakeLists.txt

Makefile

binding.gyp

build.yaml

config.m4

doc/PROTOCOL-WEB.md

gRPC-Core.podspec

grpc.gemspec

include/grpc++/impl/codegen/completion_queue.h

include/grpc++/support/channel_arguments.h

include/grpc/impl/codegen/connectivity_state.h

include/grpc/impl/codegen/grpc_types.h

include/grpc/impl/codegen/port_platform.h

include/grpc/support/log.h

include/grpc/support/string_util.h

package.xml

src/core/ext/census/census_log.h

src/core/ext/census/mlog.h

src/core/ext/client_channel/client_channel.c