This updates VideoReceiveStream2::Stop() to symmetrically tear down state that's built up in VideoReceiveStream2::Start(). Bug: webrtc:11993, webrtc:14486 Change-Id: I41f4feea5584e5baaeed2143432136f8b9761321 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/272537 Commit-Queue: Tomas Gunnarsson <tommi@webrtc.org> Reviewed-by: Danil Chapovalov <danilchap@webrtc.org> Cr-Commit-Position: refs/heads/main@{#38244}