Revert of Plumb activation time to main (patchset #16 id:280001 of https://codereview.chromium.org/2778223005/ )

Reason for revert:
Failure observed in LayerTreeHostProxyTestActivationTime.RunMultiThread_DelegatingRenderer

https://luci-logdog.appspot.com/v/?s=chromium%2Fbb%2Fchromium.win%2FWin7_Tests__dbg__1_%2F59244%2F%2B%2Frecipes%2Fsteps%2Fcc_unittests%2F0%2Flogs%2FLayerTreeHostProxyTestActivationTime.RunMultiThread_DelegatingRenderer%2F0

Original issue's description:
> Plumb activation time in cc to Blink Scheduler in Main
>
> BUG=657826,657825
> CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
>
> Review-Url: https://codereview.chromium.org/2778223005
> Cr-Commit-Position: refs/heads/master@{#465701}
> Committed: https://chromium.googlesource.com/chromium/src/+/9a2eb472fde51de48c095c9c208101c534ac211e

[email protected],[email protected],[email protected],[email protected],[email protected],[email protected]
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=657826,657825

Review-Url: https://codereview.chromium.org/2833603002
Cr-Commit-Position: refs/heads/master@{#465757}
15 files changed