Rework dispatchEvent so it is consistent for isTrusted support.

Source/modules/notifications/Notification.h

 /*
  * Copyright (C) 2013 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 87 matching lines @@
     KURL iconURL() const { return m_iconUrl; }
     SerializedScriptValue* serializedData() const { return m_serializedData.get(); }
 
     static String permissionString(WebNotificationPermission);
     static String permission(ExecutionContext*);
     static WebNotificationPermission checkPermission(ExecutionContext*);
     static void requestPermission(ExecutionContext*, NotificationPermissionCallback* = nullptr);
 
     // EventTarget interface.
     ExecutionContext* executionContext() const final { return ActiveDOMObject::executionContext(); }
-    bool dispatchEvent(PassRefPtrWillBeRawPtr<Event>) final;
     const AtomicString& interfaceName() const override;
 
     // ActiveDOMObject interface.
     void stop() override;
     bool hasPendingActivity() const override;
 
     DECLARE_VIRTUAL_TRACE();
 
+protected:
+    // EventTarget interface.
+    bool dispatchEventInternal(PassRefPtrWillBeRawPtr<Event>) final;
+
 private:
     Notification(const String& title, ExecutionContext*);
 
     void scheduleShow();
 
     // Calling show() may start asynchronous operation. If this object has
     // a V8 wrapper, hasPendingActivity() prevents the wrapper from being
     // collected while m_state is Showing, and so this instance stays alive
     // until the operation completes. Otherwise, you need to hold a ref on this
     // instance until the operation completes.
@@ skipping 39 matching lines @@
     void setState(NotificationState state) { m_state = state; }
 
     NotificationState m_state;
 
     AsyncMethodRunner<Notification> m_asyncRunner;
 };
 
 } // namespace blink
 
 #endif // Notification_h