This is a better solution than https://webrtc-review.googlesource.com/c/src/+/129929 (which got reverted).
This CL instead filters out unused SSRCs from RtpConfig for RtpVideoSender.
Bug: webrtc:10485
Change-Id: Iaa8d07681419a2387c8253eb38e08a0828e9e688
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/130505
Reviewed-by: Niels Moller <nisse@webrtc.org>
Reviewed-by: Erik Språng <sprang@webrtc.org>
Commit-Queue: Ilya Nikolaevskiy <ilnik@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#27433}