Notification should not leak document.

Source/modules/notifications/Notification.cpp

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2009, 2011, 2012 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
@@ skipping 181 matching lines @@
 void Notification::finalize()
 {
     if (m_state == Closed)
         return;
     m_state = Closed;
     unsetPendingActivity(this);
 }
 
 void Notification::dispatchShowEvent()
 {
+#if ENABLE(LEGACY_NOTIFICATIONS)
+    dispatchEvent(Event::create(eventNames().displayEvent, false, false));
+#endif
     dispatchEvent(Event::create(eventNames().showEvent, false, false));
 }
 
 void Notification::dispatchClickEvent()
 {
+    UserGestureIndicator gestureIndicator(DefinitelyProcessingNewUserGesture);
     WindowFocusAllowedIndicator windowFocusAllowed;
     dispatchEvent(Event::create(eventNames().clickEvent, false, false));
 }
 
 void Notification::dispatchCloseEvent()
 {
     dispatchEvent(Event::create(eventNames().closeEvent, false, false));
     finalize();
 }
 
 void Notification::dispatchErrorEvent()
 {
     dispatchEvent(Event::create(eventNames().errorEvent, false, false));
 }
 
 #if ENABLE(NOTIFICATIONS)
 void Notification::taskTimerFired(Timer<Notification>* timer)
 {
     ASSERT(scriptExecutionContext()->isDocument());
     ASSERT_UNUSED(timer, timer == m_taskTimer.get());
     show();
 }
 #endif
 
+bool Notification::dispatchEvent(PassRefPtr<Event> event)
+{
+    // Do not dispatch if the context is gone.
+    if (!scriptExecutionContext())
+        return false;
+
+    return EventTarget::dispatchEvent(event);
+}
 
 #if ENABLE(NOTIFICATIONS)
 const String& Notification::permission(ScriptExecutionContext* context)
 {
     ASSERT(toDocument(context)->page());
     return permissionString(NotificationController::from(toDocument(context)->page())->client()->checkPermission(context));
 }
 
 const String& Notification::permissionString(NotificationClient::Permission permission)
 {
@@ skipping 17 matching lines @@
 void Notification::requestPermission(ScriptExecutionContext* context, PassRefPtr<NotificationPermissionCallback> callback)
 {
     ASSERT(toDocument(context)->page());
     NotificationController::from(toDocument(context)->page())->client()->requestPermission(context, callback);
 }
 #endif
 
 } // namespace WebCore
 
 #endif // ENABLE(NOTIFICATIONS) || ENABLE(LEGACY_NOTIFICATIONS)