GitLab

1. re-landing the change of
https://chromium-review.googlesource.com/c/chromium/src/+/812264
2. Add a mojo call IsAuthenticating to check the authentication state
in ash lock screen.

Bug: 781998
Change-Id: I40a985cced8fe9cdaad404b068ffeacc669677a4
Reviewed-on: https://chromium-review.googlesource.com/816022
Commit-Queue: Xiaoyin Hu <xiaoyinh@chromium.org>
Reviewed-by: Toni Barzic <tbarzic@chromium.org>
Reviewed-by: James Cook <jamescook@chromium.org>
Reviewed-by: Jacob Dufault <jdufault@chromium.org>
Reviewed-by: Achuith Bhandarkar <achuith@chromium.org>
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Cr-Commit-Position: refs/heads/master@{#523474}