*** DO NOT LAND *** Attempt to understand Regions complexity

Source/core/rendering/RootInlineBox.h

 /*
  * Copyright (C) 2003, 2006, 2007, 2008 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.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 11 matching lines @@
 #define RootInlineBox_h
 
 #include "core/rendering/InlineFlowBox.h"
 #include "platform/text/BidiContext.h"
 
 namespace WebCore {
 
 class EllipsisBox;
 class HitTestResult;
 class RenderBlockFlow;
-class RenderRegion;
 
 struct BidiStatus;
 struct GapRects;
 
 class RootInlineBox : public InlineFlowBox {
 public:
     explicit RootInlineBox(RenderBlockFlow*);
 
     virtual void destroy() OVERRIDE FINAL;
 
@@ skipping 14 matching lines @@
 
     LayoutUnit paginationStrut() const { return m_fragmentationData ? m_fragmentationData->m_paginationStrut : LayoutUnit(0); }
     void setPaginationStrut(LayoutUnit strut) { ensureLineFragmentationData()->m_paginationStrut = strut; }
 
     bool isFirstAfterPageBreak() const { return m_fragmentationData ? m_fragmentationData->m_isFirstAfterPageBreak : false; }
     void setIsFirstAfterPageBreak(bool isFirstAfterPageBreak) { ensureLineFragmentationData()->m_isFirstAfterPageBreak = isFirstAfterPageBreak; }
 
     LayoutUnit paginatedLineWidth() const { return m_fragmentationData ? m_fragmentationData->m_paginatedLineWidth : LayoutUnit(0); }
     void setPaginatedLineWidth(LayoutUnit width) { ensureLineFragmentationData()->m_paginatedLineWidth = width; }
 
-    RenderRegion* containingRegion() const;
-    void setContainingRegion(RenderRegion*);
-
     LayoutUnit selectionTop() const;
     LayoutUnit selectionBottom() const;
     LayoutUnit selectionHeight() const { return max<LayoutUnit>(0, selectionBottom() - selectionTop()); }
 
     LayoutUnit selectionTopAdjustedForPrecedingBlock() const;
     LayoutUnit selectionHeightAdjustedForPrecedingBlock() const { return max<LayoutUnit>(0, selectionBottom() - selectionTopAdjustedForPrecedingBlock()); }
 
     int blockDirectionPointInLine() const;
 
     LayoutUnit alignBoxesInBlockDirection(LayoutUnit heightOfBlock, GlyphOverflowAndFallbackFontsMap&, VerticalPositionCache&);
@@ skipping 136 matching lines @@
     LayoutUnit m_lineTop;
     LayoutUnit m_lineBottom;
 
     LayoutUnit m_lineTopWithLeading;
     LayoutUnit m_lineBottomWithLeading;
 
     struct LineFragmentationData {
         WTF_MAKE_NONCOPYABLE(LineFragmentationData); WTF_MAKE_FAST_ALLOCATED;
     public:
         LineFragmentationData()
-            : m_containingRegion(0)
-            , m_paginationStrut(0)
+            : m_paginationStrut(0)
             , m_paginatedLineWidth(0)
             , m_isFirstAfterPageBreak(false)
         {
 
         }
 
         // It should not be assumed the |containingRegion| is always valid.
         // It can also be 0 if the flow has no region chain.
-        RenderRegion* m_containingRegion;
         LayoutUnit m_paginationStrut;
         LayoutUnit m_paginatedLineWidth;
         bool m_isFirstAfterPageBreak;
     };
 
     OwnPtr<LineFragmentationData> m_fragmentationData;
 
     // Floats hanging off the line are pushed into this vector during layout. It is only
     // good for as long as the line has not been marked dirty.
     OwnPtr<Vector<RenderBox*> > m_floats;
 };
 
 } // namespace WebCore
 
 #endif // RootInlineBox_h