Include Event.h in fewer header files

Source/core/html/HTMLDialogElement.cpp

 /*
  * Copyright (C) 2012 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 12 matching lines @@
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "config.h"
 #include "core/html/HTMLDialogElement.h"
 
 #include "bindings/v8/ExceptionState.h"
 #include "core/accessibility/AXObjectCache.h"
 #include "core/dom/ExceptionCode.h"
 #include "core/dom/NodeTraversal.h"
+#include "core/events/Event.h"
 #include "core/html/HTMLFormControlElement.h"
 #include "core/frame/FrameView.h"
 #include "core/rendering/RenderBlock.h"
 #include "core/rendering/style/RenderStyle.h"
 
 namespace WebCore {
 
 using namespace HTMLNames;
 
 // This function chooses the focused element when showModal() is invoked, as described in the spec for showModal().
@@ skipping 153 matching lines @@
 {
     if (event->type() == EventTypeNames::cancel) {
         closeDialog();
         event->setDefaultHandled();
         return;
     }
     HTMLElement::defaultEventHandler(event);
 }
 
 } // namespace WebCore