Some libraries hooking into WebRTC still manage to have the conference mode flag enabled on non screenshare sources resulting in a bad rate allocation. Bug: webrtc:11310 Change-Id: Id5205affb562511eda40c460e380c105d8589c51 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/182003 Reviewed-by: Erik Språng <sprang@webrtc.org> Commit-Queue: Florent Castelli <orphis@webrtc.org> Cr-Commit-Position: refs/heads/master@{#31965}