GitLab

This CL adds the first version of identity pill -- only the triggering
logic to show and to hide the pill. No animation nor UI changes are
included in this CL.

Bug: 967317
Change-Id: I76c98e9963ba97606bc9458eb111d3a6bc0872ae
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1679764Reviewed-by: Thomas Tangl <tangltom@chromium.org>
Commit-Queue: Jan Krcal <jkrcal@chromium.org>
Cr-Commit-Position: refs/heads/master@{#682648}