(The time-related first part of it, anyway.)

"proto" and "*.egg-info/" are no longer generated, "src/" can be
narrowed to "/src/", and "*_pb2.py" and "*_pb2_grpc.py" are covered by
.gitignore files in parent directories.

Fix Objective C memory leak GRPCOpSendMetadata

Document error unref contract for iomgr cb's and transport/stream errors

fixes #11473

Avoid pollution from ares.h into the global space.

Destroy byte buffer to avoid leak in zombied calls

Fix handling of send_message before send_initial_metadata in compress filter.

Fix bad_ping

Update PHP protoc plugin generation

Handle cancel correctly

Lint progress.

Remove remaining thrift-based code from main repo

Deprecated-on-arrival: Re-enable public constructor for ClientAsyncResponseReader 

Add support for Trailers-Only responses.

- When receiving a Trailers-Only response, return the metadata as
  trailing metadata instead of initial metadata.
- Send Trailers-Only response when we have no non-default initial metadata,
  no message to send, and trailing metadata to send.

Re-enable public constructor for ClientAsyncResponseReader to avoid busting client that bypassed code generator. This code is deprecated-on-arrival as it is a performance pessimization. This code path should not be used.

Remove long long

Still create channel if remotedb is false. Just do not use it in the …

Tracing Overhaul