This is preparatory to ensuring that transport-cc gets turned off when RFC8888 ccfb is negotiated. Bug: webrtc:378698658 Change-Id: Ie76677bd6aa046701562bbd93d8489858488f863 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/368543 Reviewed-by: Per Kjellander <perkj@webrtc.org> Commit-Queue: Harald Alvestrand <hta@webrtc.org> Cr-Commit-Position: refs/heads/main@{#43426}