GitLab

Introduce a LegacyExtensionMessageBubbleViewBrowserTest class that
disables the Extensions Menu UI. This allows us to migrate these tests
to the new UI in a piecemeal fashion.

This CL only introduces the class and makes all existing tests use it;
follow-ups will migrate specific tests to run with the new UI.

Bug: 1100412
Change-Id: I180ac73740a3576b467521d4b40d9ab4ec0cb9d3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2392748
Commit-Queue: Devlin <rdevlin.cronin@chromium.org>
Reviewed-by: Peter Boström <pbos@chromium.org>
Cr-Commit-Position: refs/heads/master@{#804504}