Move DOMTimer to not be a subclass of PausableTimer

Timers are already scheduled using the kJavascriptTimer task queue
which gets paused. So there is no need to iterate pausable objects
cancelling them and rescheduling them.

BUG=907125

Change-Id: I3831a1b6530bb1ab7c9b0ed80eb073dd468e38bf
Reviewed-on: https://chromium-review.googlesource.com/c/1377132
Commit-Queue: Dave Tapuska <dtapuska@chromium.org>
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Reviewed-by: Alexander Timin <altimin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#617870}
2 files changed