Cleanup <static_cast>: Switch to toFoo for Accessibility Objects.

Source/core/accessibility/AccessibilityScrollView.cpp

 /*
  * Copyright (C) 2011 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:
  *
  * 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 110 matching lines @@
         m_children[pos]->detachFromParent();
         m_children.remove(pos);
     }
 }
 
 AccessibilityScrollbar* AccessibilityScrollView::addChildScrollbar(Scrollbar* scrollbar)
 {
     if (!scrollbar)
         return 0;
 
-    AccessibilityScrollbar* scrollBarObject = static_cast<AccessibilityScrollbar*>(axObjectCache()->getOrCreate(scrollbar));
+    AccessibilityScrollbar* scrollBarObject = toAccessibilityScrollbar(axObjectCache()->getOrCreate(scrollbar));
     scrollBarObject->setParent(this);
     m_children.append(scrollBarObject);
     return scrollBarObject;
 }
 
 void AccessibilityScrollView::clearChildren()
 {
     AccessibilityObject::clearChildren();
     m_verticalScrollbar = 0;
     m_horizontalScrollbar = 0;
@@ skipping 91 matching lines @@
     return m_scrollView;
 }
 
 void AccessibilityScrollView::scrollTo(const IntPoint& point) const
 {
     if (m_scrollView)
         m_scrollView->setScrollPosition(point);
 }
 
 } // namespace WebCore