GitLab

Add previous and next track buttons to the media
notification.

BUG=893296

Change-Id: I2918e82bfa3ef11ce65e0fd8d21783e683cd3203
Reviewed-on: https://chromium-review.googlesource.com/c/1300114
Commit-Queue: Becca Hughes <beccahughes@chromium.org>
Reviewed-by: James Cook <jamescook@chromium.org>
Reviewed-by: Trent Apted <tapted@chromium.org>
Reviewed-by: Evan Stade <estade@chromium.org>
Cr-Commit-Position: refs/heads/master@{#606289}