Improve handling of dictionary conversions.

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 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 "core/events/MessageEvent.h"
 
+#include "bindings/v8/ExceptionMessages.h"
 #include "core/events/ThreadLocalEventNames.h"
 #include "core/frame/DOMWindow.h"
 
 namespace WebCore {
 
 static inline bool isValidSource(EventTarget* source)
 {
     return !source || source->toDOMWindow() || source->toMessagePort();
 }
 
@@ skipping 85 matching lines @@
     , m_dataAsArrayBuffer(data)
     , m_origin(origin)
 {
     ScriptWrappable::init(this);
 }
 
 MessageEvent::~MessageEvent()
 {
 }
 
+PassRefPtr<MessageEvent> MessageEvent::create(const AtomicString& type, const MessageEventInit& initializer, ExceptionState& exceptionState)
+{
+    if (initializer.source.get() && !isValidSource(initializer.source.get())) {
+        exceptionState.throwTypeError(ExceptionMessages::failedToConstruct("MessageEvent", "The optional 'source' property is neither a Window nor MessagePort."));
+        return 0;
+    }
+    return adoptRef(new MessageEvent(type, initializer));
+}
+
 void MessageEvent::initMessageEvent(const AtomicString& type, bool canBubble, bool cancelable, const String& origin, const String& lastEventId, DOMWindow* source, PassOwnPtr<MessagePortArray> ports)
 {
     if (dispatched())
         return;
 
     initEvent(type, canBubble, cancelable);
 
     m_dataType = DataTypeScriptValue;
     m_origin = origin;
     m_lastEventId = lastEventId;
@@ skipping 23 matching lines @@
 {
     return EventNames::MessageEvent;
 }
 
 void MessageEvent::entangleMessagePorts(ExecutionContext* context)
 {
     m_ports = MessagePort::entanglePorts(*context, m_channels.release());
 }
 
 } // namespace WebCore