Merge github.com:grpc/grpc into slice_with_exec_ctx

Makefile

gRPC-Core.podspec

src/core/ext/transport/cronet/transport/cronet_transport.c

src/core/lib/iomgr/wakeup_fd_pipe.c

src/core/lib/security/transport/handshake.c

...e-c/tests/CoreCronetEnd2EndTests/CoreCronetEnd2EndTests.m

src/proto/grpc/testing/control.proto

src/proto/grpc/testing/stats.proto

templates/gRPC-Core.podspec.template

test/core/end2end/end2end_nosec_tests.c

test/core/end2end/end2end_tests.c

test/core/end2end/gen_build_yaml.py

test/core/end2end/tests/authority_not_supported.c

test/cpp/qps/driver.cc

test/cpp/qps/qps_json_driver.cc

test/cpp/qps/report.cc

test/cpp/qps/report.h

test/cpp/qps/server.h

test/cpp/qps/usage_timer.cc

test/cpp/qps/usage_timer.h