Introduce DEFINE_CUSTOM_FONT_DATA_TYPE_CASTS, and use it

Source/core/css/CSSValue.cpp

 /*
  * Copyright (C) 2011 Andreas Kling (kling@webkit.org)
  *
  * 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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 390 matching lines @@
         delete toCSSSVGDocumentValue(this);
         return;
     }
     ASSERT_NOT_REACHED();
 }
 
 void CSSValue::finalizeGarbageCollectedObject()
 {
     if (m_isTextClone) {
         ASSERT(isCSSOMSafe());
-        static_cast<TextCloneCSSValue*>(this)->~TextCloneCSSValue();
+        toTextCloneCSSValue(this)->~TextCloneCSSValue();
         return;
     }
     ASSERT(!isCSSOMSafe() || isSubtypeExposedToCSSOM());
 
     switch (classType()) {
     case AspectRatioClass:
         toCSSAspectRatioValue(this)->~CSSAspectRatioValue();
         return;
     case BorderImageSliceClass:
         toCSSBorderImageSliceValue(this)->~CSSBorderImageSliceValue();
@@ skipping 83 matching lines @@
         toCSSSVGDocumentValue(this)->~CSSSVGDocumentValue();
         return;
     }
     ASSERT_NOT_REACHED();
 }
 
 void CSSValue::trace(Visitor* visitor)
 {
     if (m_isTextClone) {
         ASSERT(isCSSOMSafe());
-        static_cast<TextCloneCSSValue*>(this)->traceAfterDispatch(visitor);
+        toTextCloneCSSValue(this)->traceAfterDispatch(visitor);
         return;
     }
     ASSERT(!isCSSOMSafe() || isSubtypeExposedToCSSOM());
 
     switch (classType()) {
     case AspectRatioClass:
         toCSSAspectRatioValue(this)->traceAfterDispatch(visitor);
         return;
     case BorderImageSliceClass:
         toCSSBorderImageSliceValue(this)->traceAfterDispatch(visitor);
@@ skipping 104 matching lines @@
         return toCSSTransformValue(this)->cloneForCSSOM();
     case ImageSetClass:
         return toCSSImageSetValue(this)->cloneForCSSOM();
     default:
         ASSERT(!isSubtypeExposedToCSSOM());
         return TextCloneCSSValue::create(classType(), cssText());
     }
 }
 
 }