GitLab

This CL includes:
- Notify Quick Answers client when there is a network error.
- Show an error message when notified that there is a error. (UI and
message is not final).

Bug: 1047042
Test: Unit tests
Change-Id: I2e9c3618ef1965d2fe94cc10b04a9851fc7f366a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2029246Reviewed-by: Avi Drissman <avi@chromium.org>
Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Commit-Queue: Li Lin <llin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#737142}