Move the exception logic to the AudioNode creator

third_party/WebKit/Source/modules/webaudio/GainNode.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 41 matching lines @@
 
     float m_lastGain; // for de-zippering
     RefPtr<AudioParamHandler> m_gain;
 
     AudioFloatArray m_sampleAccurateGainValues;
 };
 
 class GainNode final : public AudioNode {
     DEFINE_WRAPPERTYPEINFO();
 public:
-    static GainNode* create(AbstractAudioContext&, float sampleRate);
+    static GainNode* create(AbstractAudioContext&, ExceptionState&);
     DECLARE_VIRTUAL_TRACE();
 
     AudioParam* gain() const;
 
 private:
-    GainNode(AbstractAudioContext&, float sampleRate);
+    GainNode(AbstractAudioContext&);
 
     Member<AudioParam> m_gain;
 };
 
 } // namespace blink
 
 #endif // GainNode_h