Bug 847839 - Part 1a: Port XUL Fennec's VideoPlayer to Native Fennec. r=mfinkle

--HG--
rename : embedding/android/VideoPlayer.java => mobile/android/base/VideoPlayer.java
rename : embedding/android/resources/layout/videoplayer.xml => mobile/android/base/resources/layout/videoplayer.xml
Bug 847839 - Part 1b: Clean up VideoPlayer.java style nits. r=mfinkle
Bug 847839 - Part 2: Remove obsolete files for Android XUL Fennec. r=mfinkle