Reason for revert:
Causes problems with TSAN: https://bugs.chromium.org/p/webrtc/issues/detail?id=7325
Original issue's description:
> Reland of rewrite frame generator capturer to use TaskQueue instead of EventTimeWrapper.
>
> Fix CallPerfTest.ReceivesCpuOveruseAndUnderuse to not fail on Android with new FrameGeneratorCapturer.
>
> BUG=webrtc:7301
>
> Review-Url: https://codereview.webrtc.org/2745583006
> Cr-Commit-Position: refs/heads/master@{#17168}
> Committed: b00742508aTBR=stefan@webrtc.org,tommi@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=webrtc:7301
Review-Url: https://codereview.webrtc.org/2743993002
Cr-Commit-Position: refs/heads/master@{#17173}