Rework dispatchEvent so it is consistent for isTrusted support.

Source/core/events/EventTarget.h

Index: Source/core/events/EventTarget.h
diff --git a/Source/core/events/EventTarget.h b/Source/core/events/EventTarget.h
index bad0e5631bb9ceb76311879e18e60e3357658caa..423015163d4b1137aea235cd58d5d82c78ab57b9 100644
--- a/Source/core/events/EventTarget.h
+++ b/Source/core/events/EventTarget.h
@@ -125,7 +125,8 @@ public:
     virtual bool addEventListener(const AtomicString& eventType, PassRefPtr<EventListener>, bool useCapture);
     virtual bool removeEventListener(const AtomicString& eventType, PassRefPtr<EventListener>, bool useCapture);
     virtual void removeAllEventListeners();
-    virtual bool dispatchEvent(PassRefPtrWillBeRawPtr<Event>);
+
+    bool dispatchEvent(PassRefPtrWillBeRawPtr<Event>);
 
     // dispatchEventForBindings is intended to only be called from
     // javascript originated calls. This method will validate and may adjust
@@ -152,6 +153,8 @@ public:
 protected:
     EventTarget();
 
+    virtual bool dispatchEventInternal(PassRefPtrWillBeRawPtr<Event>);
+
     // Subclasses should likely not override these themselves; instead, they should subclass EventTargetWithInlineData.
     virtual EventTargetData* eventTargetData() = 0;
     virtual EventTargetData& ensureEventTargetData() = 0;