Merge "stagefright: notify async release complete" into rvc-dev am: 3244d0db am: d0ac7b8a am: 0eba4cf5 am: 67b1aea3

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/av/+/11795217

Change-Id: I02ab90e2b5f0416f3ddf6b5e7236b261b9eb0950