Get rid of isWritingModeRoot.

sky/engine/core/rendering/RenderBox.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 2006, 2007 Apple Inc. All rights reserved.
  *
  * 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 491 matching lines @@
     void removeFloatingOrPositionedChildFromBlockLists();
 
     RenderLayer* enclosingFloatPaintingLayer() const;
 
     virtual int firstLineBoxBaseline() const { return -1; }
     virtual int inlineBlockBaseline(LineDirectionMode) const { return -1; } // Returns -1 if we should skip this box when computing the baseline of an inline-block.
 
     bool shrinkToAvoidFloats() const;
     virtual bool avoidsFloats() const;
 
-    bool isWritingModeRoot() const { return false; }
-
     bool isFlexItemIncludingDeprecated() const { return !isInline() && !isFloatingOrOutOfFlowPositioned() && parent() && parent()->isFlexibleBox(); }
 
     virtual LayoutUnit lineHeight(bool firstLine, LineDirectionMode, LinePositionMode = PositionOnContainingLine) const override;
     virtual int baselinePosition(FontBaseline, bool firstLine, LineDirectionMode, LinePositionMode = PositionOnContainingLine) const override;
 
     virtual LayoutUnit offsetLeft() const override;
     virtual LayoutUnit offsetTop() const override;
 
     // These represent your location relative to your container as a physical offset.
     // In layout related methods you almost always want the logical location (e.g. x() and y()).
@@ skipping 233 matching lines @@
         if (UNLIKELY(inlineBoxWrapper() != 0))
             deleteLineBoxWrapper();
     }
 
     ensureRareData().m_inlineBoxWrapper = boxWrapper;
 }
 
 } // namespace blink
 
 #endif // RenderBox_h