GitLab

Added an AlertCoordinator to the BrowserContainerCoordinator, which
will be used to handle link-generation failures coming from the
LinkToTextMediator. Added a UserAction for when the user presses on the
Share Page button of that alert.

Bug: 1136043
Change-Id: I7e4e6c84000a7c760e46b8b7d5251c2de7e9c79e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2495262
Auto-Submit: Sebastien Lalancette <seblalancette@chromium.org>
Commit-Queue: Jesse Doherty <jwd@chromium.org>
Reviewed-by: Jesse Doherty <jwd@chromium.org>
Reviewed-by: Rohit Rao <rohitrao@chromium.org>
Reviewed-by: sebsg <sebsg@chromium.org>
Cr-Commit-Position: refs/heads/master@{#821796}