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

Source/core/rendering/RenderView.h

Index: Source/core/rendering/RenderView.h
diff --git a/Source/core/rendering/RenderView.h b/Source/core/rendering/RenderView.h
index d4a0a792e94010fec0d89e800b5a58c0b8245ae3..3abe9a11fa998a230c9831f2367db4c2e62d2311 100644
--- a/Source/core/rendering/RenderView.h
+++ b/Source/core/rendering/RenderView.h
@@ -31,7 +31,6 @@
 
 namespace WebCore {
 
-class FlowThreadController;
 class RenderLayerCompositor;
 class RenderQuote;
 
@@ -171,12 +170,6 @@ public:
     // 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; }
@@ -190,8 +183,6 @@ public:
     void removeRenderCounter() { ASSERT(m_renderCounterCount > 0); m_renderCounterCount--; }
     bool hasRenderCounters() { return m_renderCounterCount; }
 
-    virtual void addChild(RenderObject* newChild, RenderObject* beforeChild = 0) OVERRIDE;
-
     virtual bool backgroundIsKnownToBeOpaqueInRect(const LayoutRect& localRect) const OVERRIDE;
 
     double layoutViewportWidth() const;
@@ -215,12 +206,11 @@ private:
     bool pushLayoutState(RenderBox* renderer, const LayoutSize& offset, LayoutUnit pageHeight = 0, bool pageHeightChanged = false, ColumnInfo* colInfo = 0)
     {
         // We push LayoutState even if layoutState is disabled because it stores layoutDelta too.
-        if (!doingFullRepaint() || m_layoutState->isPaginated() || renderer->hasColumns() || renderer->flowThreadContainingBlock()
+        if (!doingFullRepaint() || m_layoutState->isPaginated() || renderer->hasColumns()
             || m_layoutState->lineGrid() || (renderer->style()->lineGrid() != RenderStyle::initialLineGrid() && renderer->isRenderBlockFlow())
             || (renderer->isRenderBlock() && toRenderBlock(renderer)->shapeInsideInfo())
             || (m_layoutState->shapeInsideInfo() && renderer->isRenderBlock() && !toRenderBlock(renderer)->allowsShapeInsideInfoSharing(m_layoutState->shapeInsideInfo()->owner()))
             ) {
-            pushLayoutStateForCurrentFlowThread(renderer);
             m_layoutState = new LayoutState(m_layoutState, renderer, offset, pageHeight, pageHeightChanged, colInfo);
             return true;
         }
@@ -232,7 +222,6 @@ private:
         LayoutState* state = m_layoutState;
         m_layoutState = state->m_next;
         delete state;
-        popLayoutStateForCurrentFlowThread();
     }
 
     // Suspends the LayoutState optimization. Used under transforms that cannot be represented by
@@ -244,7 +233,6 @@ private:
     void enableLayoutState() { ASSERT(m_layoutStateDisableCount > 0); m_layoutStateDisableCount--; }
 
     void layoutContent(const LayoutState&);
-    void layoutContentInAutoLogicalHeightRegions(const LayoutState&);
 #ifndef NDEBUG
     void checkLayoutState(const LayoutState&);
 #endif
@@ -252,9 +240,6 @@ private:
     void positionDialog(RenderBox*);
     void positionDialogs();
 
-    void pushLayoutStateForCurrentFlowThread(const RenderObject*);
-    void popLayoutStateForCurrentFlowThread();
-
     friend class LayoutStateMaintainer;
     friend class LayoutStateDisabler;
 
@@ -276,7 +261,6 @@ private:
     LayoutState* m_layoutState;
     unsigned m_layoutStateDisableCount;
     OwnPtr<RenderLayerCompositor> m_compositor;
-    OwnPtr<FlowThreadController> m_flowThreadController;
     RefPtr<IntervalArena> m_intervalArena;
 
     RenderQuote* m_renderQuoteHead;