Use EventHandler type instead of EventListener for event handler attributes

Source/modules/webaudio/AudioBufferSourceNode.idl

 /*
  * Copyright (C) 2010, Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1.  Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 36 matching lines @@
     [MeasureAs=WebAudioStart, ImplementedAs=startGrain] void start(double when, double grainOffset);
     [MeasureAs=WebAudioStart, ImplementedAs=startGrain] void start(double when, double grainOffset, double grainDuration);
     void stop(double when);
 
     [DeprecateAs=WebAudioLooping, ImplementedAs=loop] attribute boolean looping; // This is an alias for the .loop attribute for backwards compatibility.
 
     [MeasureAs=LegacyWebAudio] void noteOn(double when);
     [MeasureAs=LegacyWebAudio] void noteGrainOn(double when, double grainOffset, double grainDuration);
     void noteOff(double when);
 
-    attribute EventListener onended;
+    attribute EventHandler onended;
 };