This function will be used by RTCVideoEncoderFactory for converting
media::SVCScalabilityMode to webrtc::ScalabilityMode.
Bug: webrtc:41480904
Change-Id: I64d7696457705851657050d2ea2b8c1d845286e0
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/366397
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Reviewed-by: Erik Språng <sprang@webrtc.org>
Reviewed-by: Sergey Silkin <ssilkin@webrtc.org>
Commit-Queue: Henrik Boström <hbos@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#43308}