Have Frame::script() return a reference

Source/core/frame/DOMWindow.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 343 matching lines @@
     if (!m_document)
         return;
 
     m_document->setDOMWindow(this);
     if (!m_document->confusingAndOftenMisusedAttached())
         m_document->attach();
 
     if (!m_frame)
         return;
 
-    m_frame->script()->updateDocument();
+    m_frame->script().updateDocument();
     m_document->updateViewportDescription();
 
     if (m_frame->page() && m_frame->view()) {
         if (ScrollingCoordinator* scrollingCoordinator = m_frame->page()->scrollingCoordinator()) {
             scrollingCoordinator->scrollableAreaScrollbarLayerDidChange(m_frame->view(), HorizontalScrollbar);
             scrollingCoordinator->scrollableAreaScrollbarLayerDidChange(m_frame->view(), VerticalScrollbar);
             scrollingCoordinator->scrollableAreaScrollLayerDidChange(m_frame->view());
         }
     }
 
@@ skipping 1392 matching lines @@
     return static_cast<DOMWindowLifecycleNotifier*>(LifecycleContext::lifecycleNotifier());
 }
 
 PassOwnPtr<LifecycleNotifier> DOMWindow::createLifecycleNotifier()
 {
     return DOMWindowLifecycleNotifier::create(this);
 }
 
 
 } // namespace WebCore