Expand the "font" shorthand when specified using a system font keyword.

Source/core/css/parser/CSSPropertyParser.cpp

Index: Source/core/css/parser/CSSPropertyParser.cpp
diff --git a/Source/core/css/parser/CSSPropertyParser.cpp b/Source/core/css/parser/CSSPropertyParser.cpp
index 44d4a11799e1f3955d745b6643d136329b31d4bf..e4e5b3915c02dbad75061f5c99fcccbaf07aab79 100644
--- a/Source/core/css/parser/CSSPropertyParser.cpp
+++ b/Source/core/css/parser/CSSPropertyParser.cpp
@@ -55,6 +55,7 @@
 #include "core/css/CSSLineBoxContainValue.h"
 #include "core/css/CSSParserValues.h"
 #include "core/css/CSSPrimitiveValue.h"
+#include "core/css/CSSPrimitiveValueMappings.h"
 #include "core/css/CSSPropertySourceData.h"
 #include "core/css/CSSReflectValue.h"
 #include "core/css/CSSSVGDocumentValue.h"
@@ -1413,11 +1414,9 @@ bool CSSPropertyParser::parseValue(CSSPropertyID propId, bool important)
     case CSSPropertyFont:
         // [ [ 'font-style' || 'font-variant' || 'font-weight' ]? 'font-size' [ / 'line-height' ]?
         // 'font-family' ] | caption | icon | menu | message-box | small-caption | status-bar | inherit
-        if (id >= CSSValueCaption && id <= CSSValueStatusBar)
-            validPrimitive = true;
-        else
-            return parseFont(important);
-        break;
+        if (num == 1 && id >= CSSValueCaption && id <= CSSValueStatusBar)
+            return parseKeywordBasedFont(important);
+        return parseFont(important);
     case CSSPropertyListStyle:
         return parseShorthand(propId, listStyleShorthand(), important);
     case CSSPropertyWebkitColumns:
@@ -4519,6 +4518,33 @@ PassRefPtrWillBeRawPtr<CSSPrimitiveValue> CSSPropertyParser::parseBasicShape()
     return cssValuePool().createValue(shape.release());
 }
 
+// [ 'caption' | 'icon' | 'menu' | 'message-box' | 'small-caption' | 'status-bar' | '-webkit-mini-control' | '-webkit-small-control' | '-webkit-control' ]
+bool CSSPropertyParser::parseKeywordBasedFont(bool important)
+{
+    ASSERT(m_valueList->size() == 1);
+
+    CSSParserValue* value = m_valueList->valueAt(0);
+    CSSValueID id = value->id;
+    ASSERT(id >= CSSValueCaption && id <= CSSValueStatusBar);
+
+    FontDescription fontDescription;
+    RenderTheme::theme().systemFont(id, fontDescription);
+    RefPtr<CSSValueList> familyList = CSSValueList::createCommaSeparated();
+    familyList->append(cssValuePool().createFontFamilyValue(fontDescription.firstFamily().family()));
+
+    ShorthandScope scope(this, CSSPropertyFont);
+    addProperty(CSSPropertyFontFamily, familyList, important, false);
+    addProperty(CSSPropertyFontStyle, cssValuePool().createIdentifierValue(fontDescription.style() == FontStyleItalic ? CSSValueItalic : CSSValueNormal), important, false);
+    addProperty(CSSPropertyFontVariant, cssValuePool().createIdentifierValue(fontDescription.variant() == FontVariantSmallCaps ? CSSValueSmallCaps : CSSValueNormal), important, false);
+    addProperty(CSSPropertyFontWeight, cssValuePool().createValue(fontDescription.weight()), important, false);
+    CSSParserValue fontSizeValue;
+    fontSizeValue.setFromNumber(fontDescription.specifiedSize(), CSSPrimitiveValue::CSS_PX);
+    addProperty(CSSPropertyFontSize, parseValidPrimitive(fontSizeValue.id, &fontSizeValue), important, false);
+    addProperty(CSSPropertyLineHeight, cssValuePool().createIdentifierValue(CSSValueNormal), important, false);
+
+    return true;
+}
+
 // [ 'font-style' || 'font-variant' || 'font-weight' ]? 'font-size' [ / 'line-height' ]? 'font-family'
 bool CSSPropertyParser::parseFont(bool important)
 {