Add expansion of shorthands with custom properties to longhands using a pending substition value.

third_party/WebKit/Source/core/css/CSSValue.h

 /*
  * (C) 1999-2003 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008 Apple Inc. 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.
  *
  * This library is distributed in the hope that it will be useful,
@@ skipping 80 matching lines @@
     bool isCubicBezierTimingFunctionValue() const { return m_classType == CubicBezierTimingFunctionClass; }
     bool isStepsTimingFunctionValue() const { return m_classType == StepsTimingFunctionClass; }
     bool isGridTemplateAreasValue() const { return m_classType == GridTemplateAreasClass; }
     bool isSVGDocumentValue() const { return m_classType == CSSSVGDocumentClass; }
     bool isContentDistributionValue() const { return m_classType == CSSContentDistributionClass; }
     bool isUnicodeRangeValue() const { return m_classType == UnicodeRangeClass; }
     bool isGridLineNamesValue() const { return m_classType == GridLineNamesClass; }
     bool isCustomPropertyDeclaration() const { return m_classType == CustomPropertyDeclarationClass; }
     bool isVariableReferenceValue() const { return m_classType == VariableReferenceClass; }
     bool isGridAutoRepeatValue() const { return m_classType == GridAutoRepeatClass; }
+    bool isPendingSubstitutionValue() const { return m_classType == PendingSubstitutionValueClass; }
 
     bool hasFailedOrCanceledSubresources() const;
 
     bool equals(const CSSValue&) const;
 
     void finalizeGarbageCollectedObject();
     DEFINE_INLINE_TRACE_AFTER_DISPATCH() { }
     DECLARE_TRACE();
 
     // ~CSSValue should be public, because non-public ~CSSValue causes C2248
@@ skipping 45 matching lines @@
         InitialClass,
         UnsetClass,
 
         ReflectClass,
         ShadowClass,
         UnicodeRangeClass,
         GridTemplateAreasClass,
         PathClass,
         VariableReferenceClass,
         CustomPropertyDeclarationClass,
+        PendingSubstitutionValueClass,
 
         // SVG classes.
         CSSSVGDocumentClass,
 
         CSSContentDistributionClass,
 
         // List class types must appear after ValueListClass.
         ValueListClass,
         FunctionClass,
         ImageSetClass,
@@ skipping 85 matching lines @@
         return false;
     return first->equals(*second);
 }
 
 #define DEFINE_CSS_VALUE_TYPE_CASTS(thisType, predicate) \
     DEFINE_TYPE_CASTS(thisType, CSSValue, value, value->predicate, value.predicate)
 
 } // namespace blink
 
 #endif // CSSValue_h