Expand system font values during property parsing.

Source/core/rendering/RenderThemeChromiumMac.h

 /*
  * This file is part of the theme implementation for form controls in WebCore.
  *
  * Copyright (C) 2005 Apple Computer, Inc.
  * Copyright (C) 2008, 2009 Google, 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.
@@ skipping 36 matching lines @@
     virtual Color platformActiveListBoxSelectionForegroundColor() const override;
     virtual Color platformInactiveListBoxSelectionBackgroundColor() const override;
     virtual Color platformInactiveListBoxSelectionForegroundColor() const override;
     virtual Color platformFocusRingColor() const override;
 
     virtual ScrollbarControlSize scrollbarControlSizeForPart(ControlPart part) override { return part == ListboxPart ? SmallScrollbar : RegularScrollbar; }
 
     virtual void platformColorsDidChange() override;
 
     // System fonts.
-    virtual void systemFont(CSSValueID, FontDescription&) const override;
+    virtual void systemFont(CSSValueID systemFontID, FontStyle&, FontWeight&, float& fontSize, AtomicString& fontFamily) const override;
 
     virtual int minimumMenuListSize(RenderStyle*) const override;
 
     virtual void adjustSliderThumbSize(RenderStyle*, Element*) const override;
 
     virtual IntSize sliderTickSize() const override;
     virtual int sliderTickOffsetFromTrackCenter() const override;
 
     virtual int popupInternalPaddingLeft(RenderStyle*) const override;
     virtual int popupInternalPaddingRight(RenderStyle*) const override;
@@ skipping 132 matching lines @@
     mutable RetainPtr<NSTextFieldCell> m_textField;
 
     mutable HashMap<int, RGBA32> m_systemColorCache;
 
     RetainPtr<WebCoreRenderThemeNotificationObserver> m_notificationObserver;
 };
 
 } // namespace blink
 
 #endif // RenderThemeChromiumMac_h