frameworks/base: Fix for force close during rapid FF of cetain midi clips

-Rapid fast forward of certain midi clips result in force close
message and music app exits.
-setDataSource and prepare fail in playback complete state of
media player
-Return error when setDataSource and prepare are called in playback
complete state.

Change-Id: Ie7cf80a36400db833b6e6d7c162f8a8f8eee2e5e
CRs-Fixed: 260087