GitLab

Revert of Remove fallback tick software draw. (patchset #3 id:100001 of https://codereview.chromium.org/1428263003/ )

Reason for revert:
Causes scheduler to stop activating after clearView is called. PrepareTiles is required to advance the scheduler, so draws are currently needed.

crbug.com/558743

Original issue's description:
> Remove fallback tick software draw.
>
> The fallback software draw was needed to allow the scheduler to advance
> in cases where the WebView is detached or offscreen. Because it is now
> possible for the pending tree to activate without a draw, the fallback
> tick is no longer needed in order for VisualStateListener callbacks
> to fire.
>
> BUG=431166
>
> Committed: https://crrev.com/9addff46d3bc49f8d04e43eeb3f55e01a4982a00
> Cr-Commit-Position: refs/heads/master@{#358156}

TBR=boliu@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=431166

Review URL: https://codereview.chromium.org/1474653002

Cr-Commit-Position: refs/heads/master@{#361334}