Related: #3871
Motivation:
StreamBufferingEncoderTest does not release when writeGoAway() is
called.
Modifications:
Release the buffer in mock object arguments
Result:
No buffer leak
Motivation:
gRPC's BufferingHttp2ConnectionEncoder is a generic utility that simplifies client-side applications that want to allow stream creation without worrying about violating the SETTINGS_MAX_CONCURRENT_STREAMS limit. Since it's not gRPC-specific it makes sense to move it into Netty proper.
Modifications:
Adding the BufferingHttp2ConnectionEncoder and it's unit test.
Result:
Netty now supports buffering stream creation.
