Position video overlay only when video is ready

Get rid of the hacky wait x seconds to see if dragabbleDiv's content changes in size to recalculate div's initial position. Instead only show draggableDiv and calculate initial position when video has been rendered (is ready to play).

Test: Manually
Change-Id: Ifce81aaa5a0a26475dee70e4b9ad4afdd004e116
4 files changed