CSSValue Immediates: Replace CSSPrimitiveValue usage with const references

Source/core/css/StylePropertySerializer.cpp

 /*
  * (C) 1999-2003 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2011 Research In Motion Limited. All rights reserved.
  * Copyright (C) 2013 Intel Corporation. All rights reserved.
  *
  * 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 640 matching lines @@
                     || shorthand.properties()[propertyIndex + 1] == CSSPropertyWebkitMaskRepeatY);
                 NullableCSSValue yValue = values[propertyIndex + 1]->isValueList() ?
                     toCSSValueList(values[propertyIndex + 1])->item(layer) : values[propertyIndex + 1];
 
 
                 // FIXME: At some point we need to fix this code to avoid returning an invalid shorthand,
                 // since some longhand combinations are not serializable into a single shorthand.
                 if (!value->isPrimitiveValue() || !yValue->isPrimitiveValue())
                     continue;
 
-                CSSValueID xId = toCSSPrimitiveValue(*value).getValueID();
-                CSSValueID yId = toCSSPrimitiveValue(*yValue).getValueID();
+                CSSValueID xId = toCSSPrimitiveValue(value).getValueID();
+                CSSValueID yId = toCSSPrimitiveValue(yValue).getValueID();
                 // Maybe advance propertyIndex to look at the next CSSValue in the list for the checks below.
                 if (xId == yId) {
                     useSingleWordShorthand = true;
                     property = shorthand.properties()[++propertyIndex];
                 } else if (xId == CSSValueRepeat && yId == CSSValueNoRepeat) {
                     useRepeatXShorthand = true;
                     property = shorthand.properties()[++propertyIndex];
                 } else if (xId == CSSValueNoRepeat && yId == CSSValueRepeat) {
                     useRepeatYShorthand = true;
                     property = shorthand.properties()[++propertyIndex];
@@ skipping 288 matching lines @@
             isInitialValue = false;
         if (!value->isInheritedValue())
             isInheritedValue = false;
         if (isImportant != m_propertySet.propertyIsImportant(shorthand.properties()[i]))
             return false;
     }
     return isInitialValue || isInheritedValue;
 }
 
 }