GitLab

Refactor RunLoop::RunUntilIdle call in a while loop into an observer
class that only hold one RunLoop.

RunLoop::RunUntilIdle in a while loop may never return in multithread
context on Android platform.

Bug: 786626
Change-Id: Ic5deb53e892d9c6303346eb6a7f803c89eddd26d
Reviewed-on: https://chromium-review.googlesource.com/882183
Commit-Queue: Xing Liu <xingliu@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Reviewed-by: Min Qin <qinmin@chromium.org>
Reviewed-by: David Trainor <dtrainor@chromium.org>
Cr-Commit-Position: refs/heads/master@{#532011}