Move generic shorthand serialization checks out of specific routines

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

 /*
  * (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 30 matching lines @@
     String getPropertyValue(CSSPropertyID) const;
 private:
     String getCommonValue(const StylePropertyShorthand&) const;
     String borderPropertyValue() const;
     String getLayeredShorthandValue(const StylePropertyShorthand&) const;
     String get4Values(const StylePropertyShorthand&) const;
     String borderSpacingValue(const StylePropertyShorthand&) const;
     String getShorthandValue(const StylePropertyShorthand&, String separator = " ") const;
     String fontValue() const;
     String fontVariantValue() const;
-    void appendFontLonghandValueIfNotNormal(CSSPropertyID, StringBuilder& result, String& value) const;
+    void appendFontLonghandValueIfNotNormal(CSSPropertyID, StringBuilder& result) const;
     String backgroundRepeatPropertyValue() const;
     String getPropertyText(CSSPropertyID, const String& value, bool isImportant, bool isNotFirstDecl) const;
     bool isPropertyShorthandAvailable(const StylePropertyShorthand&) const;
     bool shorthandHasOnlyInitialOrInheritedValue(const StylePropertyShorthand&) const;
     void appendBackgroundPropertyAsText(StringBuilder& result, unsigned& numDecls) const;
 
+    // This function does checks common to all shorthands, and returns:
+    // - The serialization if the shorthand serializes as a css-wide keyword.
+    // - An empty string if either some longhands are not set, the important
+    // flag is not set consistently, or css-wide keywords are used. In these
+    // cases serialization will always fail.
+    // - A null string otherwise.
+    String commonShorthandChecks(const StylePropertyShorthand&) const;
+
     // Only StylePropertySerializer uses the following two classes.
     class PropertyValueForSerializer {
         STACK_ALLOCATED();
     public:
         explicit PropertyValueForSerializer(StylePropertySet::PropertyReference property)
             : m_value(property.value())
             , m_id(property.id())
             , m_isImportant(property.isImportant())
             , m_isImplicit(property.isImplicit())
             , m_isInherited(property.isInherited()) { }
@@ skipping 47 matching lines @@
         std::bitset<numCSSProperties> m_longhandPropertyUsed;
         bool m_needToExpandAll;
     };
 
     const StylePropertySetForSerializer m_propertySet;
 };
 
 } // namespace blink
 
 #endif // StylePropertySerializer_h