MediaPlayerService: avoid invalid static cast am: ee0a0e39ac am: 7b6a85546c am: b07255f603 am: d560830823 am: 51efd24460 am: 8d32201d4a am: 2b5ee9c8e4
am: 17744ab9d7

Change-Id: I7c9bff5b79002b4c1e83437b69c8cfd5a09854a3