Serialize font shorthand as empty string if any longhand is not specified

third_party/WebKit/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 491 matching lines @@
     String horizontalValueCSSText = horizontalValue->cssText();
     String verticalValueCSSText = verticalValue->cssText();
     if (horizontalValueCSSText == verticalValueCSSText)
         return horizontalValueCSSText;
     return horizontalValueCSSText + ' ' + verticalValueCSSText;
 }
 
 void StylePropertySerializer::appendFontLonghandValueIfNotNormal(CSSPropertyID propertyID, StringBuilder& result, String& commonValue) const
 {
     int foundPropertyIndex = m_propertySet.findPropertyIndex(propertyID);
-    if (foundPropertyIndex == -1)
-        return;
+    ASSERT(foundPropertyIndex != -1);
 
     const CSSValue* val = m_propertySet.propertyAt(foundPropertyIndex).value();
     if (val->isPrimitiveValue() && toCSSPrimitiveValue(val)->getValueID() == CSSValueNormal) {
         commonValue = String();
         return;
     }
 
     char prefix = '\0';
     switch (propertyID) {
     case CSSPropertyFontStyle:
@@ skipping 14 matching lines @@
     if (prefix && !result.isEmpty())
         result.append(prefix);
     String value = m_propertySet.propertyAt(foundPropertyIndex).value()->cssText();
     result.append(value);
     if (!commonValue.isNull() && commonValue != value)
         commonValue = String();
 }
 
 String StylePropertySerializer::fontValue() const
 {
+    if (!isPropertyShorthandAvailable(fontShorthand()) && !shorthandHasOnlyInitialOrInheritedValue(fontShorthand()))
+        return emptyString();
+
     int fontSizePropertyIndex = m_propertySet.findPropertyIndex(CSSPropertyFontSize);
     int fontFamilyPropertyIndex = m_propertySet.findPropertyIndex(CSSPropertyFontFamily);
-    if (fontSizePropertyIndex == -1 || fontFamilyPropertyIndex == -1)
-        return emptyString();
+    ASSERT(fontSizePropertyIndex != -1 && fontFamilyPropertyIndex != -1);
 
     PropertyValueForSerializer fontSizeProperty = m_propertySet.propertyAt(fontSizePropertyIndex);
     PropertyValueForSerializer fontFamilyProperty = m_propertySet.propertyAt(fontFamilyPropertyIndex);
 
     String commonValue = fontSizeProperty.value()->cssText();
     StringBuilder result;
     appendFontLonghandValueIfNotNormal(CSSPropertyFontStyle, result, commonValue);
     appendFontLonghandValueIfNotNormal(CSSPropertyFontVariant, result, commonValue);
     appendFontLonghandValueIfNotNormal(CSSPropertyFontWeight, result, commonValue);
     appendFontLonghandValueIfNotNormal(CSSPropertyFontStretch, result, commonValue);
@@ skipping 429 matching lines @@
             isInitialValue = false;
         if (!value->isInheritedValue())
             isInheritedValue = false;
         if (isImportant != m_propertySet.propertyIsImportant(shorthand.properties()[i]))
             return false;
     }
     return isInitialValue || isInheritedValue;
 }
 
 }