Cleanup: Start using toFoo methods as part of newly adopted coding guideline.

Source/core/rendering/RenderTheme.cpp

 /**
  * This file is part of the theme implementation for form controls in WebCore.
  *
  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2012 Apple Computer, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 809 matching lines @@
         return false;
     return o->node()->active();
 }
 
 bool RenderTheme::isSpinUpButtonPartPressed(const RenderObject* o) const
 {
     Node* node = o->node();
     if (!node || !node->active() || !node->isElementNode()
         || !toElement(node)->isSpinButtonElement())
         return false;
-    SpinButtonElement* element = static_cast<SpinButtonElement*>(node);
+    SpinButtonElement* element = toSpinButtonElement(node);
     return element->upDownState() == SpinButtonElement::Up;
 }
 
 bool RenderTheme::isReadOnlyControl(const RenderObject* o) const
 {
     Node* node = o->node();
     if (!node || !node->isElementNode())
         return false;
     return toElement(node)->matchesReadOnlyPseudoClass();
 }
 
 bool RenderTheme::isHovered(const RenderObject* o) const
 {
     Node* node = o->node();
     if (!node)
         return false;
     if (!node->isElementNode() || !toElement(node)->isSpinButtonElement())
         return node->hovered();
-    SpinButtonElement* element = static_cast<SpinButtonElement*>(node);
+    SpinButtonElement* element = toSpinButtonElement(node);
     return element->hovered() && element->upDownState() != SpinButtonElement::Indeterminate;
 }
 
 bool RenderTheme::isSpinUpButtonPartHovered(const RenderObject* o) const
 {
     Node* node = o->node();
     if (!node || !node->isElementNode() || !toElement(node)->isSpinButtonElement())
         return false;
-    SpinButtonElement* element = static_cast<SpinButtonElement*>(node);
+    SpinButtonElement* element = toSpinButtonElement(node);
     return element->upDownState() == SpinButtonElement::Up;
 }
 
 #if !USE(NEW_THEME)
 
 void RenderTheme::adjustCheckboxStyle(RenderStyle* style, Element*) const
 {
     // A summary of the rules for checkbox designed to match WinIE:
     // width/height - honored (WinIE actually scales its control for small widths, but lets it overflow for small heights.)
     // font-size - not honored (control has no text), but we use it to decide which control size to use.
@@ skipping 509 matching lines @@
 
     // padding - not honored by WinIE, needs to be removed.
     style->resetPadding();
 
     // border - honored by WinIE, but looks terrible (just paints in the control box and turns off the Windows XP theme)
     // for now, we will not honor it.
     style->resetBorder();
 }
 
 } // namespace WebCore