Convert tests to new error scheme

Makefile

build.yaml

src/core/ext/client_config/channel_connectivity.c

src/core/ext/client_config/client_channel.c

src/core/ext/client_config/subchannel.c

src/core/ext/client_config/subchannel_call_holder.c

src/core/ext/lb_policy/pick_first/pick_first.c

src/core/ext/lb_policy/round_robin/round_robin.c

...core/ext/transport/chttp2/server/insecure/server_chttp2.c

...ext/transport/chttp2/server/secure/server_secure_chttp2.c

src/core/ext/transport/chttp2/transport/chttp2_transport.c

src/core/ext/transport/chttp2/transport/frame_data.c

src/core/ext/transport/chttp2/transport/hpack_parser.c

src/core/ext/transport/chttp2/transport/parsing.c

src/core/lib/iomgr/closure.c

src/core/lib/iomgr/error.c

src/core/lib/iomgr/error.h

src/core/lib/iomgr/exec_ctx.c

src/core/lib/iomgr/tcp_server_posix.c

src/core/lib/iomgr/timer.c