https://bugs.webkit.org/show_bug.cgi?id=105959

Reviewed by Adam Barth.

Add OVERRIDE to all dispatchEvent overrides and use "using" instead of
reimplementing EventTarget::dispatchEvent in subclasses where having the
virtual override of dispatchEvent hides the overloads in
the superclass.

No new tests, just refactoring.

* Modules/indexeddb/IDBDatabase.h:
(IDBDatabase):
* Modules/indexeddb/IDBOpenDBRequest.h:
(IDBOpenDBRequest):
* Modules/indexeddb/IDBRequest.h:
(IDBRequest):
* Modules/indexeddb/IDBTransaction.h:
(IDBTransaction):
* dom/EventDispatchMediator.h:
(FocusEventDispatchMediator):
(BlurEventDispatchMediator):
* dom/GestureEvent.h:
(GestureEventDispatchMediator):
* dom/KeyboardEvent.h:
(KeyboardEventDispatchMediator):
* dom/MouseEvent.h:
* dom/Node.h:
(Node):
* dom/UIEvent.h:
(FocusInEventDispatchMediator):
(FocusOutEventDispatchMediator):
* dom/WheelEvent.h:
(WheelEventDispatchMediator):
* html/HTMLMediaElement.h:
* html/track/TextTrackCue.cpp:
* html/track/TextTrackCue.h:
(TextTrackCue):
* page/DOMWindow.h:
(DOMWindow):
* svg/SVGElementInstance.h:
(SVGElementInstance):


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@138674 268f45cc-cd09-0410-ab3c-d52691b4dbfc