Ensure that ArrayBuffers actively being used by the Web Audio API cannot be neutered

Source/wtf/ArrayBufferContents.h

 /*
  * Copyright (C) 2009 Apple Inc. All rights reserved.
  * Copyright (C) 2013 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
@@ skipping 42 matching lines @@
 
     void clear();
 
     void* data() const { return m_data; }
     unsigned sizeInBytes() const { return m_sizeInBytes; }
 
     bool hasDeallocationObserver() const { return !!m_deallocationObserver; }
     void setDeallocationObserver(ArrayBufferDeallocationObserver* observer) { m_deallocationObserver = observer; }
 
     void transfer(ArrayBufferContents& other);
+    void copyTo(ArrayBufferContents& other);
 
     static bool allocateMemory(size_t, InitializationPolicy, void*& data);
     static void freeMemory(void* data);
 
 private:
     void* m_data;
     unsigned m_sizeInBytes;
     ArrayBufferDeallocationObserver* m_deallocationObserver;
 };
 
 } // namespace WTF
 
 #endif // ArrayBufferContents_h