Have DOMWindow deal with references instead of pointers when possible

Source/modules/screen_orientation/ScreenOrientationController.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "modules/screen_orientation/ScreenOrientationController.h"
 
 #include "core/dom/Document.h"
 #include "core/events/Event.h"
 #include "core/frame/DOMWindow.h"
@@ skipping 20 matching lines @@
 ScreenOrientationController::ScreenOrientationController(Document& document)
     : m_document(document)
     , m_orientation(blink::WebScreenOrientationPortraitPrimary)
 {
     // FIXME: We should listen for screen orientation change events only when the page is visible.
     ScreenOrientationDispatcher::instance().addController(this);
 }
 
 void ScreenOrientationController::dispatchOrientationChangeEvent()
 {
-    if (m_document.domWindow() && m_document.domWindow()->screen()
+    if (m_document.domWindow()
         && !m_document.activeDOMObjectsAreSuspended()
         && !m_document.activeDOMObjectsAreStopped())
-        m_document.domWindow()->screen()->dispatchEvent(Event::create(EventTypeNames::orientationchange));
+        m_document.domWindow()->screen().dispatchEvent(Event::create(EventTypeNames::orientationchange));
 }
 
 const char* ScreenOrientationController::supplementName()
 {
     return "ScreenOrientationController";
 }
 
 void ScreenOrientationController::didChangeScreenOrientation(blink::WebScreenOrientation orientation)
 {
     if (orientation == m_orientation)
         return;
 
     m_orientation = orientation;
     dispatchOrientationChangeEvent();
 }
 
 } // namespace WebCore