This is a reland of 4de2be99.

Original change's description:
> [test] Move timeout control to timeout processor
> 
> Bug: v8:6917
> Change-Id: I03be38be952f0d59eb20fa98102ef09ca795de40
> Reviewed-on: https://chromium-review.googlesource.com/883446
> Commit-Queue: Michał Majewski <majeski@google.com>
> Reviewed-by: Michael Achenbach <machenbach@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#50848}

Bug: v8:6917
Change-Id: I52798af84991d4815910e9da5f4837329cdb3c96
Reviewed-on: https://chromium-review.googlesource.com/885765Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Michał Majewski <majeski@google.com>
Cr-Commit-Position: refs/heads/master@{#50870}