Make sure to use CSSValueID and CSSPropertyID rather than integers.

Source/core/css/CSSPrimitiveValue.h

 /*
  * (C) 1999-2003 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2008 Apple Inc. All rights reserved.
  * Copyright (C) 2007 Alexey Proskuryakov <ap@webkit.org>
  *
  * 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.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Library General Public License for more details.
  *
  * You should have received a copy of the GNU Library General Public License
  * along with this library; see the file COPYING.LIB.  If not, write to
  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  * Boston, MA 02110-1301, USA.
  */
 
 #ifndef CSSPrimitiveValue_h
 #define CSSPrimitiveValue_h
 
+#include "CSSValueKeywords.h"
 #include "core/css/CSSValue.h"
 #include "core/platform/graphics/Color.h"
-#include <wtf/Forward.h>
-#include <wtf/MathExtras.h>
-#include <wtf/PassRefPtr.h>
+#include "wtf/Forward.h"
+#include "wtf/MathExtras.h"
+#include "wtf/PassRefPtr.h"
 
 namespace WebCore {
 
 class CSSCalcValue;
 class Counter;
 class Pair;
 class Quad;
 class RGBColor;
 class Rect;
 class RenderStyle;
@@ skipping 335 matching lines @@
     ASSERT_WITH_SECURITY_IMPLICATION(!value || value->isPrimitiveValue());
     return static_cast<const CSSPrimitiveValue*>(value);
 }
 
 // Catch unneeded cast.
 void toCSSPrimitiveValue(const CSSPrimitiveValue*);
 
 } // namespace WebCore
 
 #endif // CSSPrimitiveValue_h