Split "Online" and "Offline" AudioContext processing

Source/modules/webaudio/AudioScheduledSourceNode.h

 /*
  * Copyright (C) 2012 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
@@ skipping 15 matching lines @@
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #ifndef AudioScheduledSourceNode_h
 #define AudioScheduledSourceNode_h
 
 #include "modules/webaudio/AudioSourceNode.h"
 
 namespace blink {
 
+class AbstractAudioContext;
 class AudioBus;
 
 class AudioScheduledSourceHandler : public AudioHandler {
 public:
     // These are the possible states an AudioScheduledSourceNode can be in:
     //
     // UNSCHEDULED_STATE - Initial playback state. Created, but not yet scheduled.
     // SCHEDULED_STATE - Scheduled to play (via start()), but not yet playing.
     // PLAYING_STATE - Generating sound.
     // FINISHED_STATE - Finished generating sound.
@@ skipping 58 matching lines @@
 public:
     void start(ExceptionState&);
     void start(double when, ExceptionState&);
     void stop(ExceptionState&);
     void stop(double when, ExceptionState&);
 
     EventListener* onended();
     void setOnended(PassRefPtr<EventListener>);
 
 protected:
-    explicit AudioScheduledSourceNode(AudioContext&);
+    explicit AudioScheduledSourceNode(AbstractAudioContext&);
     AudioScheduledSourceHandler& audioScheduledSourceHandler() const;
 };
 
 } // namespace blink
 
 #endif // AudioScheduledSourceNode_h