All valid scalability modes should be supported by the builtin software decoder/encoder. Bug: chromium:1187565 Change-Id: If66105d210d5055019f35dae2f80a18ad4a70cdd Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/222642 Commit-Queue: Johannes Kron <kron@webrtc.org> Reviewed-by: Danil Chapovalov <danilchap@webrtc.org> Reviewed-by: Erik Språng <sprang@webrtc.org> Cr-Commit-Position: refs/heads/main@{#34998}