Generate toCSSFooValue() for CSS child values

Source/core/css/CSSValue.cpp

Index: Source/core/css/CSSValue.cpp
diff --git a/Source/core/css/CSSValue.cpp b/Source/core/css/CSSValue.cpp
index e6fbb54fb1cb9f2dccbae7548d1a4282b7055f90..4c231b900d218d6844955de4ba16e5fc19f6841f 100644
--- a/Source/core/css/CSSValue.cpp
+++ b/Source/core/css/CSSValue.cpp
@@ -406,7 +406,7 @@ void CSSValue::destroy()
         delete toCSSValueList(this);
         return;
     case CSSTransformClass:
-        delete static_cast<CSSTransformValue*>(this);
+        delete toCSSTransformValue(this);
         return;
     case LineBoxContainClass:
         delete static_cast<CSSLineBoxContainValue*>(this);
@@ -418,13 +418,13 @@ void CSSValue::destroy()
         delete toCSSImageSetValue(this);
         return;
     case CSSFilterClass:
-        delete static_cast<CSSFilterValue*>(this);
+        delete toCSSFilterValue(this);
         return;
     case CSSArrayFunctionValueClass:
-        delete static_cast<CSSArrayFunctionValue*>(this);
+        delete toCSSArrayFunctionValue(this);
         return;
     case CSSMixFunctionValueClass:
-        delete static_cast<CSSMixFunctionValue*>(this);
+        delete toCSSMixFunctionValue(this);
         return;
     case CSSShaderClass:
         delete toCSSShaderValue(this);