- Rename member variable and access functions to show connection to the
extmap-allow-mixed attribute.
- Transfer extmap-allow-mixed setting when new content is added to a
SessionDescription.
- Add boolean function that shows support of extmap-allow-mixed.
- Add unit tests of extmap-allow-mixed logic.
Bug: webrtc:7990
Change-Id: Ic330fbab7be3e1df81c2d36ce522acc254617178
Reviewed-on: https://webrtc-review.googlesource.com/c/105308
Reviewed-by: Seth Hampson <shampson@webrtc.org>
Commit-Queue: Johannes Kron <kron@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#25163}
