Ownership of the retransmission rate limiter for video is moved from send side congestion controller to Call. This is to reduce the interface on the rtp transport controller send. Bug: webrtc:8415 Change-Id: Ie9c7317400a9eb61a3c8325b9e527844ffc13769 Reviewed-on: https://webrtc-review.googlesource.com/58745 Commit-Queue: Sebastian Jansson <srte@webrtc.org> Reviewed-by: Stefan Holmer <stefan@webrtc.org> Reviewed-by: Erik Språng <sprang@webrtc.org> Cr-Commit-Position: refs/heads/master@{#22254}