GitLab

Add new polymer class oobe-carousel. Oobe-carousel is responsible for
showing slides in a carousel.

- Animation is done as all slides stand in a circle.
- Navigation bar consists of left and right arrows and non-accessible
  dots which indicate an active slide.
- Autotransition is supported only if ChromeVox is not enabled.

Fixed: 1104887
Change-Id: I5c2332d6cde470479c13d2297458213deb0faa4c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2294664
Commit-Queue: Roman Aleksandrov <raleksandrov@google.com>
Reviewed-by: Denis Kuznetsov [CET] <antrim@chromium.org>
Cr-Commit-Position: refs/heads/master@{#799210}