[Media Controls] toggle native controls with separate logic

Completely separate current controls and native controls.
Only have basic control functions in native controls.
(implemented previous video and next video in this CL as well)
Will continue adding back features in follow up CLs

Bug: 909963
Change-Id: If14ea5a33b07070f16c760763b2770a952012180
Reviewed-on: https://chromium-review.googlesource.com/c/1383148
Commit-Queue: Jazz Xu <jazzhsu@chromium.org>
Reviewed-by: Yoshiki Iguchi <yoshiki@chromium.org>
Reviewed-by: Tommy Steimel <steimel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#623799}
4 files changed