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

Source/modules/webaudio/DelayProcessor.h

Index: Source/modules/webaudio/DelayProcessor.h
diff --git a/Source/modules/webaudio/DelayProcessor.h b/Source/modules/webaudio/DelayProcessor.h
index 5b2a5e44f2c405cf3c166c41cbce6ede2d58ee9f..b74e3327ecdc267206cd49f792e558932b42068c 100644
--- a/Source/modules/webaudio/DelayProcessor.h
+++ b/Source/modules/webaudio/DelayProcessor.h
@@ -38,6 +38,7 @@ class DelayProcessor FINAL : public AudioDSPKernelProcessor {
 public:
     DelayProcessor(AudioContext*, float sampleRate, unsigned numberOfChannels, double maxDelayTime);
     virtual ~DelayProcessor();
+    virtual void trace(Visitor*) OVERRIDE;
 
     virtual PassOwnPtr<AudioDSPKernel> createKernel() OVERRIDE;
 
@@ -46,7 +47,7 @@ public:
     double maxDelayTime() { return m_maxDelayTime; }
 private:
 
-    RefPtrWillBePersistent<AudioParam> m_delayTime;
+    RefPtrWillBeMember<AudioParam> m_delayTime;
     double m_maxDelayTime;
 };