stagefright: stop audio source if player fails to start

Change-Id: I70083f8bfe8409283e52eea017d27d94767c5244
Merge "stagefright: stop audio source if player fails to start" into cm-11.0
Merge branch 'cm-11.0' of git://github.com/CyanogenMod/android_frameworks_av into cm-11.0