GitLab

Add double tap gesture recognition to MediaControlOverlayPlayButton so
it can detect double tap gestures on the side and jump accordingly. Adds
LayoutTests as a virtual test suite so they are tested with the modern
media controls flag on.

BUG=779989

TBR=jbroman@chromium.org

Change-Id: I2d6e3c79d5ca3b447eda70f35da3dd22283a14b3
Reviewed-on: https://chromium-review.googlesource.com/800150
Commit-Queue: Becca Hughes <beccahughes@chromium.org>
Reviewed-by: Mounir Lamouri <mlamouri@chromium.org>
Cr-Commit-Position: refs/heads/master@{#522139}