commit 6589def397b2685e617260ee0004fbc969a266aa
author Tommi <tommi@webrtc.org> Thu Feb 17 22:36:47 2022
committer WebRTC LUCI CQ <webrtc-scoped@luci-project-accounts.iam.gserviceaccount.com> Wed Feb 23 11:10:32 2022
tree 287c7413909a0ed5b8fd447e16bd6f20f140d2ff
parent 3b393ec991ed26a36195c9f41e74b0d7d72e6953

Align sender/receiver teardown in RtpTransceiver.

This makes SetChannel() consistently make 2 invokes instead of a
multiple of senders+receivers (previous minimum was 4 but could be
larger).

* Stop() doesn't hop to the worker thread.
* SetMediaChannel(), an already-required step on the worker thread for
  senders and *sometimes* for receivers[1], is now consistently required
  for both. This simplifies transceiver teardown and enables the next
  bullet.
* Transceiver stops all senders and receivers in one go rather than
  ping ponging between threads.

[1] When not required, it was done implicitly inside of Stop().
  See changes in `RtpTransceiver::SetChannel`

Bug: webrtc:13540
Change-Id: Ied61636c8ef09d782bf519524fff2a31e15219a8
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/249797
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Reviewed-by: Tomas Gunnarsson <tommi@webrtc.org>
Commit-Queue: Tomas Gunnarsson <tommi@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#36057}