Split up CSSPrimitiveValue::isString into isString and isCustomIdent

Source/core/css/parser/CSSPropertyParser.cpp

 /*
  * Copyright (C) 2003 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2005 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2007 Nicholas Shanks <webkit@nickshanks.com>
  * Copyright (C) 2008 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2012 Adobe Systems Incorporated. All rights reserved.
  * Copyright (C) 2012 Intel Corporation. All rights reserved.
  *
@@ skipping 3206 matching lines @@
     if (numericValue)
         values->append(numericValue.release());
     if (gridLineName)
         values->append(gridLineName.release());
     ASSERT(values->length());
     return values.release();
 }
 
 static PassRefPtrWillBeRawPtr<CSSValue> gridMissingGridPositionValue(CSSValue* value)
 {
-    if (value->isPrimitiveValue() && toCSSPrimitiveValue(value)->isString())
+    if (value->isPrimitiveValue() && toCSSPrimitiveValue(value)->isCustomIdent())
         return value;
 
     return cssValuePool().createIdentifierValue(CSSValueAuto);
 }
 
 bool CSSPropertyParser::parseGridItemPositionShorthand(CSSPropertyID shorthandId, bool important)
 {
     ShorthandScope scope(this, shorthandId);
     const StylePropertyShorthand& shorthand = shorthandForProperty(shorthandId);
     ASSERT(shorthand.length() == 2);
@@ skipping 4941 matching lines @@
         }
     }
 
     if (!list->length())
         return nullptr;
 
     return list.release();
 }
 
 } // namespace blink