This change finally wires up VideoRtpReceiver::OnGenerateKeyFrame and OnEncodedSinkEnabled into internal::VideoReceiveStream so that encoded frames can flow to sinks installed in VideoTrackSourceInterface. Bug: chromium:1013590 Change-Id: I76f8226752294aee8fe137d1a78ee66548900cc2 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/161095 Commit-Queue: Markus Handell <handellm@webrtc.org> Reviewed-by: Per Kjellander <perkj@webrtc.org> Cr-Commit-Position: refs/heads/master@{#30003}