Bug 1357639 - part3 : change audio focus state before notifying observers. r=sebastian

Notify observer might cause the method (notifyStoppedPlaying) is called by C++ side,
and we should change our internal state before calling the method.

MozReview-Commit-ID: 5xNXhGmAIrR

--HG--
extra : rebase_source : 23fb8bef4066cad5238f49bb692445d9b684a84e

mobile/android/base/java/org/mozilla/gecko/media/AudioFocusAgent.java

@@ -59,31 +59,32 @@ public class AudioFocusAgent {
                 switch (focusChange) {
                     case AudioManager.AUDIOFOCUS_LOSS:
                         Log.d(LOGTAG, "onAudioFocusChange, AUDIOFOCUS_LOSS");
+                        mAudioFocusState = State.LOST_FOCUS;
                         notifyObservers("audioFocusChanged", "lostAudioFocus");
                         notifyMediaControlService(MediaControlService.ACTION_PAUSE_BY_AUDIO_FOCUS);
-                        mAudioFocusState = State.LOST_FOCUS;
                         break;
                     case AudioManager.AUDIOFOCUS_LOSS_TRANSIENT:
                         Log.d(LOGTAG, "onAudioFocusChange, AUDIOFOCUS_LOSS_TRANSIENT");
+                        mAudioFocusState = State.LOST_FOCUS_TRANSIENT;
                         notifyObservers("audioFocusChanged", "lostAudioFocusTransiently");
                         notifyMediaControlService(MediaControlService.ACTION_PAUSE_BY_AUDIO_FOCUS);
-                        mAudioFocusState = State.LOST_FOCUS_TRANSIENT;
                         break;
                     case AudioManager.AUDIOFOCUS_LOSS_TRANSIENT_CAN_DUCK:
                         Log.d(LOGTAG, "onAudioFocusChange, AUDIOFOCUS_LOSS_TRANSIENT_CAN_DUCK");
-                        notifyMediaControlService(MediaControlService.ACTION_START_AUDIO_DUCK);
                         mAudioFocusState = State.LOST_FOCUS_TRANSIENT_CAN_DUCK;
+                        notifyMediaControlService(MediaControlService.ACTION_START_AUDIO_DUCK);
                         break;
                     case AudioManager.AUDIOFOCUS_GAIN:
-                        if (mAudioFocusState.equals(State.LOST_FOCUS_TRANSIENT_CAN_DUCK)) {
+                        State state = mAudioFocusState;
+                        mAudioFocusState = State.OWN_FOCUS;
+                        if (state.equals(State.LOST_FOCUS_TRANSIENT_CAN_DUCK)) {
                             Log.d(LOGTAG, "onAudioFocusChange, AUDIOFOCUS_GAIN (from DUCKING)");
                             notifyMediaControlService(MediaControlService.ACTION_STOP_AUDIO_DUCK);
-                        } else if (mAudioFocusState.equals(State.LOST_FOCUS_TRANSIENT)) {
+                        } else if (state.equals(State.LOST_FOCUS_TRANSIENT)) {
                             Log.d(LOGTAG, "onAudioFocusChange, AUDIOFOCUS_GAIN");
                             notifyObservers("audioFocusChanged", "gainAudioFocus");
                             notifyMediaControlService(MediaControlService.ACTION_RESUME_BY_AUDIO_FOCUS);
                         }
-                        mAudioFocusState = State.OWN_FOCUS;
                         break;
                     default:
                 }