vp9 encoder wrapper rely on that behaviour to generate vp9-specific temporal references Bug: webrtc:11999 Change-Id: I35536af4eca76450e2f72777e06ad3af872a5800 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/211340 Commit-Queue: Danil Chapovalov <danilchap@webrtc.org> Reviewed-by: Philip Eliasson <philipel@webrtc.org> Cr-Commit-Position: refs/heads/master@{#33445}