bindings: Supports reentrance to ScriptWrappable::wrap through V8DOMWrapper::createWrapper.

Source/core/dom/DOMDataView.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "core/dom/DOMDataView.h"
 
 #include "bindings/core/v8/DOMDataStore.h"
 #include "bindings/core/v8/V8ArrayBuffer.h"
 #include "bindings/core/v8/V8DOMWrapper.h"
@@ skipping 53 matching lines @@
 
     ASSERT(!DOMDataStore::containsWrapper(this, isolate));
 
     const WrapperTypeInfo* wrapperTypeInfo = this->wrapperTypeInfo();
     v8::Local<v8::Value> v8Buffer = toV8(buffer(), creationContext, isolate);
     if (v8Buffer.IsEmpty())
         return v8::Handle<v8::Object>();
     ASSERT(v8Buffer->IsArrayBuffer());
 
     v8::Local<v8::Object> wrapper = v8::DataView::New(v8Buffer.As<v8::ArrayBuffer>(), byteOffset(), byteLength());
+    // V8::DataView::New may run an arbitrary script and it may result in
+    // creating a new wrapper and associating it with |this|.  If so, the
+    // wrapper already created and associated must be used.
+    v8::Local<v8::Object> associatedWrapper = DOMDataStore::getWrapper(this, isolate);
+    if (UNLIKELY(!associatedWrapper.IsEmpty()))
+        return associatedWrapper;
 
     return associateWithWrapper(isolate, wrapperTypeInfo, wrapper);
 }
 
 v8::Local<v8::Object> DOMDataView::associateWithWrapper(v8::Isolate* isolate, const WrapperTypeInfo* wrapperTypeInfo, v8::Local<v8::Object> wrapper)
 {
     return V8DOMWrapper::associateObjectWithWrapper(isolate, this, wrapperTypeInfo, wrapper);
 }
 
 } // namespace blink