Oilpan: WebAudio: Prepare to move AudioProcessor hierarchy to Oilpan heap.

Source/platform/audio/AudioProcessor.h

 /*
  * 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 14 matching lines @@
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #ifndef AudioProcessor_h
 #define AudioProcessor_h
 
 #include "platform/PlatformExport.h"
+#include "platform/heap/Handle.h"
 
 namespace blink {
 
 class AudioBus;
 
 // AudioProcessor is an abstract base class representing an audio signal processing object with a single input and a single output,
 // where the number of input channels equals the number of output channels.  It can be used as one part of a complex DSP algorithm,
 // or as the processor for a basic (one input - one output) AudioNode.
 
-class PLATFORM_EXPORT AudioProcessor {
+class PLATFORM_EXPORT AudioProcessor : public NoBaseWillBeGarbageCollectedFinalized<AudioProcessor> {
 public:
     AudioProcessor(float sampleRate, unsigned numberOfChannels)
         : m_initialized(false)
         , m_numberOfChannels(numberOfChannels)
         , m_sampleRate(sampleRate)
     {
     }
 
     virtual ~AudioProcessor();
+    virtual void trace(Visitor*);
 
     // Full initialization can be done here instead of in the constructor.
     virtual void initialize() = 0;
     virtual void uninitialize() = 0;
 
     // Processes the source to destination bus.  The number of channels must match in source and destination.
     virtual void process(const AudioBus* source, AudioBus* destination, size_t framesToProcess) = 0;
 
     // Resets filter state
     virtual void reset() = 0;
@@ skipping 10 matching lines @@
 
 protected:
     bool m_initialized;
     unsigned m_numberOfChannels;
     float m_sampleRate;
 };
 
 } // namespace blink
 
 #endif // AudioProcessor_h