MediaPlayerService: avoid invalid static cast am: ee0a0e39ac am: 7b6a85546c am: b07255f603 am: d560830823 am: 51efd24460 am: 8d32201d4a am: 2b5ee9c8e4 am: 17744ab9d7 am: 77da9683de
am: 739ce899e5

Change-Id: I7b90f114e40bc1349fcf1d340d9e88bdd6a91754