GitLab

This makes AshService create the necessary things when ash runs out of the
browser process.

BUG=837686
TEST=covered by tests

Change-Id: Ia7203fbde3737c8009315c19de0d3b981605eb5a
Reviewed-on: https://chromium-review.googlesource.com/1109465
Commit-Queue: Scott Violet <sky@chromium.org>
Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#569353}