The width/height of the highest simulcast layer is divisible by 2^exponent.
The exponent is allowed to be set through the field trial.
Bug: none
Change-Id: I2ec0af2deb6e3a176f705a2ad1c250a35b086701
Reviewed-on: https://webrtc-review.googlesource.com/c/104067
Reviewed-by: Stefan Holmer <stefan@webrtc.org>
Reviewed-by: Erik Språng <sprang@webrtc.org>
Reviewed-by: Rasmus Brandt <brandtr@webrtc.org>
Commit-Queue: Åsa Persson <asapersson@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#25159}