Delete remaining masks dead code.

sky/engine/core/rendering/style/RenderStyleConstants.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, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Graham Dennis (graham.dennis@gmail.com)
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ skipping 70 matching lines @@
 };
 
 enum EFillBox {
     BorderFillBox, PaddingFillBox, ContentFillBox
 };
 
 enum EFillRepeat {
     RepeatFill, NoRepeatFill, RoundFill, SpaceFill
 };
 
+// FIXME(sky): Remove this enum.
 enum EFillLayerType {
-    BackgroundFillLayer, MaskFillLayer
+    BackgroundFillLayer
 };
 
 // CSS3 Background Values
 enum EFillSizeType { Contain, Cover, SizeLength, SizeNone };
 
 // CSS3 Background Position
 enum BackgroundEdgeOrigin { TopEdge, RightEdge, BottomEdge, LeftEdge };
 
-// CSS Mask Source Types
-enum EMaskSourceType { MaskAlpha, MaskLuminance };
-
 // Deprecated Flexible Box Properties
 
 enum EBoxPack { Start, Center, End, Justify };
 enum EBoxAlignment { BSTRETCH, BSTART, BCENTER, BEND, BBASELINE };
 enum EBoxOrient { HORIZONTAL, VERTICAL };
 enum EBoxLines { SINGLE, MULTIPLE };
 enum EBoxDirection { BNORMAL, BREVERSE };
 
 // CSS3 Flexbox Properties
 
@@ skipping 321 matching lines @@
 static const float maximumAllowedFontSize = 1000000.0f;
 
 enum TextIndentLine { TextIndentFirstLine, TextIndentEachLine };
 enum TextIndentType { TextIndentNormal, TextIndentHanging };
 
 enum CSSBoxType { BoxMissing = 0, MarginBox, BorderBox, PaddingBox, ContentBox };
 
 } // namespace blink
 
 #endif  // SKY_ENGINE_CORE_RENDERING_STYLE_RENDERSTYLECONSTANTS_H_