Enable Oilpan by default for webaudio/

Source/platform/audio/AudioProcessor.h

Index: Source/platform/audio/AudioProcessor.h
diff --git a/Source/platform/audio/AudioProcessor.h b/Source/platform/audio/AudioProcessor.h
index aded735abfeddde1392db8bb80c45c182eb672b9..df94128e4d56dc94fa718cb5ac07ba36c14a22a7 100644
--- a/Source/platform/audio/AudioProcessor.h
+++ b/Source/platform/audio/AudioProcessor.h
@@ -42,7 +42,7 @@ class AudioBus;
 // 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 : public NoBaseWillBeGarbageCollectedFinalized<AudioProcessor> {
+class PLATFORM_EXPORT AudioProcessor : public GarbageCollectedFinalized<AudioProcessor> {
 public:
     AudioProcessor(float sampleRate, unsigned numberOfChannels)
         : m_initialized(false)