part 1: make camera save a poster image for videos
part 2: remove videodb from gallery app
part 3: update Gallery metadata parser to use video poster images
part 4: modify media_frame and video_player to use a poster image
part 5: update camera to use new media_frame api
part 6: modify Video to release video hardware when it changes visibility
part 7: defer Video metadata parsing so Camera has time to create poster image