Re-land: Ensure that ArrayBuffers actively being used by the Web Audio API cannot be neutered

Source/wtf/ArrayBuffer.cpp

 /*
  * Copyright (C) 2009 Apple 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 25 matching lines @@
 
 bool ArrayBuffer::transfer(ArrayBufferContents& result, Vector<RefPtr<ArrayBufferView> >& neuteredViews)
 {
     RefPtr<ArrayBuffer> keepAlive(this);
 
     if (!m_contents.data()) {
         result.clear();
         return false;
     }
 
-    m_contents.transfer(result);
+    bool allViewsAreNeuterable = true;
+    for (ArrayBufferView* i = m_firstView; i; i = i->m_nextView) {
+        if (!i->isNeuterable())
+            allViewsAreNeuterable = false;
+    }
+
+    if (allViewsAreNeuterable) {
+        m_contents.transfer(result);
+    } else {
+        m_contents.copyTo(result);
+        if (!result.data())
+            return false;
+    }
 
     while (m_firstView) {
         ArrayBufferView* current = m_firstView;
         removeView(current);
-        current->neuter();
+        if (allViewsAreNeuterable || current->isNeuterable())
+            current->neuter();
         neuteredViews.append(current);
     }
 
     m_isNeutered = true;
 
     return true;
 }
 
 void ArrayBuffer::addView(ArrayBufferView* view)
 {
@@ skipping 11 matching lines @@
     if (view->m_nextView)
         view->m_nextView->m_prevView = view->m_prevView;
     if (view->m_prevView)
         view->m_prevView->m_nextView = view->m_nextView;
     if (m_firstView == view)
         m_firstView = view->m_nextView;
     view->m_prevView = view->m_nextView = 0;
 }
 
 }