Delete remaining masks dead code.

sky/engine/core/rendering/style/StyleRareNonInheritedData.h

 /*
  * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
  *           (C) 2000 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2003, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Graham Dennis (graham.dennis@gmail.com)
  *
  * 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
@@ skipping 84 matching lines @@
 
     DataRef<StyleFilterData> m_filter; // Filter operations (url, sepia, blur, etc.)
 
     OwnPtr<CounterDirectiveMap> m_counterDirectives;
 
     RefPtr<ShadowList> m_boxShadow;
 
     OwnPtr<CSSAnimationData> m_animations;
     OwnPtr<CSSTransitionData> m_transitions;
 
-    FillLayer m_mask;
-    NinePieceImage m_maskBoxImage;
-
     LengthSize m_pageSize;
 
     RefPtr<ClipPathOperation> m_clipPath;
 
     StyleColor m_textDecorationColor;
 
     int m_order;
 
     LengthPoint m_objectPosition;
 
@@ skipping 31 matching lines @@
     unsigned m_justifySelfOverflowAlignment : 2; // OverflowAlignment
 
 private:
     StyleRareNonInheritedData();
     StyleRareNonInheritedData(const StyleRareNonInheritedData&);
 };
 
 } // namespace blink
 
 #endif  // SKY_ENGINE_CORE_RENDERING_STYLE_STYLERARENONINHERITEDDATA_H_