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* Add flag for the shelf new UI
* When it's on, center some shelf items (apps, pinned apps)
* Minor dimension and opacity tweaks when the flag is on
* Fix some minor typos here and there

Change-Id: I87b7fa819bac0fff77f5007c4a0cee760a630239
Bug: 805612
Reviewed-on: https://chromium-review.googlesource.com/1116540Reviewed-by: Michael Wasserman <msw@chromium.org>
Reviewed-by: Alex Newcomer <newcomer@chromium.org>
Commit-Queue: Manu Cornet <manucornet@chromium.org>
Cr-Commit-Position: refs/heads/master@{#572397}