GitLab

Mocks:
https://docs.google.com/presentation/d/1gJEE-qL8XCst4gIQaAXt0fmlxlHIg7HWtcw0l_ISq-s/edit#slide=id.ga480910b3a_0_40

Notes:
- We are changing the name from Chrome Labs to Chrome Beta; "Labs" and
the top area of bubble above experiments will be changed.

- Icons will be added in a later CL.

Bug: 1145666
Change-Id: I344a89efd89aff4f5fd8c782df3e21f6bdb0d419
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2616490
Commit-Queue: Elaine Chien <elainechien@chromium.org>
Reviewed-by: Peter Kasting <pkasting@chromium.org>
Cr-Commit-Position: refs/heads/master@{#841748}