Expand system font values during property parsing.

Source/core/css/StylePropertyShorthandCustom.cpp

Index: Source/core/css/StylePropertyShorthandCustom.cpp
diff --git a/Source/core/css/StylePropertyShorthandCustom.cpp b/Source/core/css/StylePropertyShorthandCustom.cpp
index 8140b8a64edebf09685b64c4cf439fb859b9d81e..3df2949bf2d3f51b2cbb9a850a8b3afc9c1e52f2 100644
--- a/Source/core/css/StylePropertyShorthandCustom.cpp
+++ b/Source/core/css/StylePropertyShorthandCustom.cpp
@@ -132,13 +132,6 @@ const StylePropertyShorthand& parsingShorthandForProperty(CSSPropertyID property
 
 bool isExpandedShorthand(CSSPropertyID id)
 {
-    // The system fonts bypass the normal style resolution by using RenderTheme,
-    // thus we need to special case it here. FIXME: This is a violation of CSS 3 Fonts
-    // as we should still be able to change the longhands.
-    // DON'T ADD ANY SHORTHAND HERE UNLESS IT ISN'T ALWAYS EXPANDED AT PARSE TIME (which is wrong).
-    if (id == CSSPropertyFont)
-        return false;
-
     return shorthandForProperty(id).length();
 }