GitLab

Add tests to verify tab sharing UI elements: infobars, contents border
and tab sharing indicator.

Bug: 996722
Change-Id: I5fa5ec7e4a48a66c1ba9b08ff76b84a105961352
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1847287Reviewed-by: Guido Urdaneta <guidou@chromium.org>
Commit-Queue: Marina Ciocea <marinaciocea@chromium.org>
Cr-Commit-Position: refs/heads/master@{#707368}