GitLab

This class will be reused in WebLayer's infobars implementation. Banners
conceptually fit well within the purpose of //components/browser_ui,
and so we move it there.

Bug: 1099169
Change-Id: I441d8e1ef310be47bca1bda8ac6c015bd96ca172
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2274503Reviewed-by: Bo <boliu@chromium.org>
Reviewed-by: Dominick Ng <dominickn@chromium.org>
Commit-Queue: Colin Blundell <blundell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#783919}