bindings: Retires manual dispatching in createV8{HTML,SVG}Wrapper, etc.

Source/core/events/MessageEvent.cpp

 /*
  * Copyright (C) 2007 Henry Mason (hmason@mac.com)
  * Copyright (C) 2003, 2005, 2006, 2007, 2008 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
@@ skipping 181 matching lines @@
 #if ENABLE(OILPAN)
     visitor->trace(m_ports);
 #endif
     Event::trace(visitor);
 }
 
 v8::Handle<v8::Object> MessageEvent::wrap(v8::Handle<v8::Object> creationContext, v8::Isolate* isolate)
 {
     v8::Handle<v8::Object> wrapper = Event::wrap(creationContext, isolate);
 
+    // Ensures a wrapper is created for the data to return now so that V8 knows how
+    // much memory is used via the wrapper. To keep the wrapper alive, it's set to
+    // the wrapper of the MessageEvent as a hidden value.
     switch (dataType()) {
     case MessageEvent::DataTypeScriptValue:
     case MessageEvent::DataTypeSerializedScriptValue:
         break;
     case MessageEvent::DataTypeString:
         V8HiddenValue::setHiddenValue(isolate, wrapper, V8HiddenValue::stringData(isolate), v8String(isolate, dataAsString()));
         break;
     case MessageEvent::DataTypeBlob:
         break;
     case MessageEvent::DataTypeArrayBuffer:
         V8HiddenValue::setHiddenValue(isolate, wrapper, V8HiddenValue::arrayBufferData(isolate), toV8(dataAsArrayBuffer(), wrapper, isolate));
         break;
     }
 
     return wrapper;
 }
 
 } // namespace blink