GitLab

This is part 2/4 CLs to move the <audio>/<video> elements off of
a synchronous API that can lead to renderer hangs and premature
audio renderer errors.

Specifically this will allow us to create AudioRendererMixerInputs
with an authorization timeout of zero when the asynchronous API
is the only one in use.

BUG=905506
TEST=compiles.
R=olka

Change-Id: I298550db1e7bac9b73033566c17cff8f1d2252b3
Reviewed-on: https://chromium-review.googlesource.com/c/1347146
Commit-Queue: Dale Curtis <dalecurtis@chromium.org>
Reviewed-by: Olga Sharonova <olka@chromium.org>
Cr-Commit-Position: refs/heads/master@{#612400}