Remove CSS regions support, keeping a bare minimum to support "region-based" multicol.

Source/core/rendering/RenderView.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  * Copyright (C) 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 156 matching lines @@
     bool usesCompositing() const;
 
     IntRect unscaledDocumentRect() const;
     LayoutRect backgroundRect(RenderBox* backgroundRenderer) const;
 
     IntRect documentRect() const;
 
     // Renderer that paints the root background has background-images which all have background-attachment: fixed.
     bool rootBackgroundIsEntirelyFixed() const;
 
-    bool hasRenderNamedFlowThreads() const;
-    bool checkTwoPassLayoutForAutoHeightRegions() const;
     FlowThreadController* flowThreadController();
 
-    virtual void styleDidChange(StyleDifference, const RenderStyle* oldStyle) OVERRIDE;
-
     IntervalArena* intervalArena();
 
     void setRenderQuoteHead(RenderQuote* head) { m_renderQuoteHead = head; }
     RenderQuote* renderQuoteHead() const { return m_renderQuoteHead; }
 
     // FIXME: This is a work around because the current implementation of counters
     // requires walking the entire tree repeatedly and most pages don't actually use either
     // feature so we shouldn't take the performance hit when not needed. Long term we should
     // rewrite the counter and quotes code.
     void addRenderCounter() { m_renderCounterCount++; }
@@ skipping 45 matching lines @@
 
     // Suspends the LayoutState optimization. Used under transforms that cannot be represented by
     // LayoutState (common in SVG) and when manipulating the render tree during layout in ways
     // that can trigger repaint of a non-child (e.g. when a list item moves its list marker around).
     // Note that even when disabled, LayoutState is still used to store layoutDelta.
     // These functions may only be accessed by LayoutStateMaintainer or LayoutStateDisabler.
     void disableLayoutState() { m_layoutStateDisableCount++; }
     void enableLayoutState() { ASSERT(m_layoutStateDisableCount > 0); m_layoutStateDisableCount--; }
 
     void layoutContent(const LayoutState&);
-    void layoutContentInAutoLogicalHeightRegions(const LayoutState&);
 #ifndef NDEBUG
     void checkLayoutState(const LayoutState&);
 #endif
 
     void positionDialog(RenderBox*);
     void positionDialogs();
 
     void pushLayoutStateForCurrentFlowThread(const RenderObject*);
     void popLayoutStateForCurrentFlowThread();
 
@@ skipping 108 matching lines @@
         if (m_view)
             m_view->enableLayoutState();
     }
 private:
     RenderView* m_view;
 };
 
 } // namespace WebCore
 
 #endif // RenderView_h