Reason for revert:
Reland with fixes to the failing perf tests.
Original issue's description:
> Revert of rewrite frame generator capturer to use TaskQueue instead of EventTimeWrapper (patchset #2 id:90001 of https://codereview.webrtc.org/2744003002/ )
>
> Reason for revert:
> CallPerfTest.ReceivesCpuOveruseAndUnderuse perf test fails due to this CL. It requires very accurate frame rate, which may not be so accurate now.
>
> Original issue's description:
> > Reland of rewrite frame generator capturer to use TaskQueue instead of EventTimeWrapper (patchset #1 id:1 of https://codereview.webrtc.org/2743993002/ )
> >
> > And enable large full-stack test depending on that change (Reland of https://codereview.webrtc.org/2741823003/)
> > TBR=stefan@webrtc.org,tommi@webrtc.org
> > BUG=webrtc:7301,webrtc:7325
> >
> > Review-Url: https://codereview.webrtc.org/2744003002
> > Cr-Commit-Position: refs/heads/master@{#17196}
> > Committed: 8c0a5896d1
>
> TBR=stefan@webrtc.org,tommi@webrtc.org,sprang@webrtc.org
> # Skipping CQ checks because original CL landed less than 1 days ago.
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
> BUG=webrtc:7301,webrtc:7325
>
> Review-Url: https://codereview.webrtc.org/2748643002
> Cr-Commit-Position: refs/heads/master@{#17198}
> Committed: 382a72a0d3
BUG=webrtc:7301,webrtc:7325
Review-Url: https://codereview.webrtc.org/2750473002
Cr-Commit-Position: refs/heads/master@{#17253}
2549ad4fef