As the send time congestion controller now has been removed, we don't need the RTP related constructs anymore. Bug: webrtc:9510 Change-Id: I02c059ed8ae907ab4672d183c5639ad459b581aa Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/142221 Commit-Queue: Sebastian Jansson <srte@webrtc.org> Reviewed-by: Björn Terelius <terelius@webrtc.org> Cr-Commit-Position: refs/heads/master@{#28330}