Add plumbing for font-stretch

Source/core/css/CSSFontValue.cpp

 /**
  * (C) 1999-2003 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2004, 2005, 2006 Apple Computer, Inc.
  *
  * 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 26 matching lines @@
     if (variant) {
         if (!result.isEmpty())
             result.append(' ');
         result.append(variant->cssText());
     }
     if (weight) {
         if (!result.isEmpty())
             result.append(' ');
         result.append(weight->cssText());
     }
+    if (stretch) {
+        if (!result.isEmpty())
+            result.append(' ');
+        result.append(stretch->cssText());
+    }
     if (size) {
         if (!result.isEmpty())
             result.append(' ');
         result.append(size->cssText());
     }
     if (lineHeight) {
         if (!size)
             result.append(' ');
         result.append('/');
         result.append(lineHeight->cssText());
     }
     if (family) {
         if (!result.isEmpty())
             result.append(' ');
         result.append(family->cssText());
     }
 
     return result.toString();
 }
 
 bool CSSFontValue::equals(const CSSFontValue& other) const
 {
     return compareCSSValuePtr(style, other.style)
         && compareCSSValuePtr(variant, other.variant)
         && compareCSSValuePtr(weight, other.weight)
+        && compareCSSValuePtr(stretch, other.stretch)
         && compareCSSValuePtr(size, other.size)
         && compareCSSValuePtr(lineHeight, other.lineHeight)
         && compareCSSValuePtr(family, other.family);
 }
 
 void CSSFontValue::traceAfterDispatch(Visitor* visitor)
 {
-
     visitor->trace(style);
     visitor->trace(variant);
     visitor->trace(weight);
+    visitor->trace(stretch);
     visitor->trace(size);
     visitor->trace(lineHeight);
     visitor->trace(family);
     CSSValue::traceAfterDispatch(visitor);
 }
 
 }