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

Source/wtf/ArrayBufferContents.cpp

 /*
  * 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 10 matching lines @@
  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "config.h"
 #include "wtf/ArrayBufferContents.h"
 
 #include "wtf/ArrayBufferDeallocationObserver.h"
+#include <string.h>
 
 namespace WTF {
 
 ArrayBufferContents::ArrayBufferContents()
     : m_data(0)
     , m_sizeInBytes(0)
     , m_deallocationObserver(0) { }
 
 ArrayBufferContents::ArrayBufferContents(unsigned numElements, unsigned elementByteSize, ArrayBufferContents::InitializationPolicy policy)
     : m_data(0)
@@ skipping 49 matching lines @@
 }
 
 void ArrayBufferContents::transfer(ArrayBufferContents& other)
 {
     ASSERT(!other.m_data);
     other.m_data = m_data;
     other.m_sizeInBytes = m_sizeInBytes;
     clear();
 }
 
+void ArrayBufferContents::copyTo(ArrayBufferContents& other)
+{
+    ASSERT(!other.m_sizeInBytes);
+    other.freeMemory(other.m_data);
+    allocateMemory(m_sizeInBytes, DontInitialize, other.m_data);
+    if (!other.m_data)
+        return;
+    memcpy(other.m_data, m_data, m_sizeInBytes);
+    other.m_sizeInBytes = m_sizeInBytes;
+}
+
 bool ArrayBufferContents::allocateMemory(size_t size, InitializationPolicy policy, void*& data)
 {
     if (policy == ZeroInitialize) {
         return WTF::tryFastCalloc(size, 1).getValue(data);
     }
     ASSERT(policy == DontInitialize);
     return WTF::tryFastMalloc(size).getValue(data);
 }
 
 void ArrayBufferContents::freeMemory(void * data)
 {
     WTF::fastFree(data);
 }
 
 } // namespace WTF