Turn on enable begin frame scheduling by default
This turns on --enable-begin-frame-scheduling[1] for all[2] platforms.
This was already on for Android so should only be a real change
for desktop / ChromeOS platforms.
Lots of cleanup can follow from this like removing all commit vsync /
authoritative vsync / CompositorVSyncManager things, but this is a
smaller patch to suss out any performance regressions.
[1] In this case, "begin frame scheduling" means browser->renderer
begin frame ticks instead of sending vsync information and having
a synthetic source on the renderer side.
[2] MUS is not hooked up to begin frame scheduling yet, but
mojo:mash_session in an "oxygen" build still works with this patch
applied. Blimp also doesn't use begin frame scheduling and will
eventually just be transitioned to a synthetic begin frame source
for its engine half.
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel
Review-Url: https://codereview.chromium.org/1939253002
Cr-Commit-Position: refs/heads/master@{#401796}
9 files changed
