Support 'paint-order' from SVG2.

Source/core/css/CSSProperty.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 453 matching lines @@
     case CSSPropertyOverflowY:
     case CSSPropertyPadding:
     case CSSPropertyPaddingBottom:
     case CSSPropertyPaddingLeft:
     case CSSPropertyPaddingRight:
     case CSSPropertyPaddingTop:
     case CSSPropertyPage:
     case CSSPropertyPageBreakAfter:
     case CSSPropertyPageBreakBefore:
     case CSSPropertyPageBreakInside:
+    case CSSPropertyPaintOrder:
     case CSSPropertyPosition:
     case CSSPropertyRight:
     case CSSPropertySize:
     case CSSPropertySrc:
     case CSSPropertyStopColor:
     case CSSPropertyStopOpacity:
     case CSSPropertyTableLayout:
     case CSSPropertyTextDecoration:
     case CSSPropertyTextDecorationLine:
     case CSSPropertyTextDecorationStyle:
@@ skipping 190 matching lines @@
         return false;
     case CSSPropertyInvalid:
         ASSERT_NOT_REACHED();
         return false;
     }
     ASSERT_NOT_REACHED();
     return false;
 }
 
 } // namespace WebCore