Merge MediaControlsAndroid into MediaControls

The additional functionality in MediaControlsAndroid is so small that
merging it was trivial. Just use CSS to hide the overlay enclosure.

One unsightly ifdef remains in MediaControls::shouldHideControls(),
hopefully this can eventually be removed by using a setting or perhaps
checking the device capabilities.

MediaControls::createTextTrackDisplay() was made simpler.

BUG=341813

Review URL: https://codereview.chromium.org/192453005

git-svn-id: svn://svn.chromium.org/blink/trunk@168967 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Use outlineBox if we have an outline

Currently we decided to repaint if the outline box has moved or if we have to
paint the background and our outline box has changed shape. This CL updates the
code to only look at the outlineBox if we have an outline.

The patch was largely done by Dan Sinclair (dsinclair@chromium.org) on
https://codereview.chromium.org/187813004/. I merely generated the test
expectations and added some code to avoid over-invalidating.

BUG=320139

Review URL: https://codereview.chromium.org/192863004

git-svn-id: svn://svn.chromium.org/blink/trunk@168968 bbb929c8-8fbe-4397-9dbb-9b2b20218538