AudioManager: fix event handler

Fix access by reference to listener list outside of
synchronized block by cloning the list.

Bug: 154341343
Test: AudioPolicyTest#testAudioPorts, AudioManagerTest#testVolumeGroupCallback, AudioRoutingTest
Change-Id: I1f0fd62c1894dc0dbb07b01f2fd78899e48b4932

media/java/android/media/AudioPortEventHandler.java

@@ -78,7 +78,8 @@ class AudioPortEventHandler {
                                     listeners.add((AudioManager.OnAudioPortUpdateListener)msg.obj);
                                 }
                             } else {
-                                listeners = mListeners;
+                                listeners = (ArrayList<AudioManager.OnAudioPortUpdateListener>)
+                                        mListeners.clone();
                             }
                         }
                         // reset audio port cache if the event corresponds to a change coming

media/java/android/media/audiopolicy/AudioVolumeGroupChangeHandler.java

@@ -80,7 +80,8 @@ public class AudioVolumeGroupChangeHandler {
                                         (AudioManager.VolumeGroupCallback) msg.obj);
                             }
                         } else {
-                            listeners = mListeners;
+                            listeners = (ArrayList<AudioManager.VolumeGroupCallback>)
+                                    mListeners.clone();
                         }
                     }
                     if (listeners.isEmpty()) {