tree f7d4647e303bcd3be922304e0c24e2f11fe514ed
parent 7484e62332d12d32a1908034fdddbb258ac7fe73
author Henrik Boström <hbos@webrtc.org> 1675866207 +0100
committer WebRTC LUCI CQ <webrtc-scoped@luci-project-accounts.iam.gserviceaccount.com> 1675933244 +0000

Add test coverage for legacy VP9 SVC with media flow.

When asking for 3 encodings of VP9, which the spec says is simulcast,
you don't get simulcast but instead you get one RTP stream sending SVC.

This results in a single "outbound-rtp" but GetParameters() still says
3 encodings are used. We know we get SVC because the scalabilityMode
from getStats() says "L3T3_KEY".

In a future CL we will add simulcast VP9 support when
`scalability_mode` is specified in the API but we'll need to continue
to support the legacy SVC code paths until that has been deprecated
and removed (https://crbug.com/webrtc/14889).

Bug: webrtc:14884
Change-Id: Ibeca44b7a0b93097ad9525e45ebbca3b7663c686
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/292581
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Reviewed-by: Evan Shrubsole <eshr@webrtc.org>
Commit-Queue: Henrik Boström <hbos@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#39278}