The same observer implementation was being used for both client and
server but the role is different (sender vs receiver), so I split
the functionality up into two separate classes.
Bug: webrtc:11547
Change-Id: Ia60ab96fb86b4ff61fa7bff5f30d59b6fe0f9746
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/300742
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Commit-Queue: Tomas Gunnarsson <tommi@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#39886}
61e8b59701