Web Audio: Don't create unnecessary DelayNode object.

Source/modules/webaudio/DelayNode.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:
  * 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 19 matching lines @@
 #include "wtf/PassRefPtr.h"
 
 namespace blink {
 
 class AudioParam;
 class ExceptionState;
 
 class DelayNode final : public AudioBasicProcessorNode {
     DEFINE_WRAPPERTYPEINFO();
 public:
-    static DelayNode* create(AudioContext* context, float sampleRate, double maxDelayTime, ExceptionState& exceptionState)
-    {
-        return new DelayNode(context, sampleRate, maxDelayTime, exceptionState);
-    }
-
+    static DelayNode* create(AudioContext*, float sampleRate, double maxDelayTime, ExceptionState&);
     AudioParam* delayTime();
 
 private:
-    DelayNode(AudioContext*, float sampleRate, double maxDelayTime, ExceptionState&);
+    DelayNode(AudioContext*, float sampleRate, double maxDelayTime);
 
     DelayProcessor* delayProcessor() { return static_cast<DelayProcessor*>(processor()); }
 };
 
 } // namespace blink
 
 #endif // DelayNode_h