Move WebMediaPlayer and friends to public/platform/

This is a prerequisite for eliminating the
MediaPlayer/MediaPlayerClient layer.

Minor style changes were needed to pass presubmit.

BUG=310466

Review URL: https://codereview.chromium.org/67083003

git-svn-id: svn://svn.chromium.org/blink/trunk@161792 bbb929c8-8fbe-4397-9dbb-9b2b20218538
6 files changed
tree: 3b86e3dffa0f98e3f14e916bd8ed86612186ab87
  1. third_party/