Merge "Fix deadlock b/w ActivityManagerService and MediaSessionService"

services/core/java/com/android/server/media/MediaSessionService.java

@@ -887,6 +887,15 @@ public class MediaSessionService extends SystemService implements Monitor {
                     }
                     return;
                 }
+
+                // Execute mAudioService.adjustSuggestedStreamVolume() on
+                // handler thread of MediaSessionService.
+                // This will release the MediaSessionService.mLock sooner and avoid
+                // a potential deadlock between MediaSessionService.mLock and
+                // ActivityManagerService lock.
+                mHandler.post(new Runnable() {
+                    @Override
+                    public void run() {
                         try {
                             String packageName = getContext().getOpPackageName();
                             mAudioService.adjustSuggestedStreamVolume(direction, suggestedStream,
@@ -894,6 +903,8 @@ public class MediaSessionService extends SystemService implements Monitor {
                         } catch (RemoteException e) {
                             Log.e(TAG, "Error adjusting default volume.", e);
                         }
+                    }
+                });
             } else {
                 session.adjustVolume(direction, flags, getContext().getPackageName(),
                         UserHandle.myUserId(), true);