Remove RenderFlowThread::offsetFromLogicalTopOfFirstRegion().

Source/core/rendering/RenderFlowThread.h

Index: Source/core/rendering/RenderFlowThread.h
diff --git a/Source/core/rendering/RenderFlowThread.h b/Source/core/rendering/RenderFlowThread.h
index ed5a6e780a10ce560078f9fa9fcd0ed68d95f1d4..e47da2b1fd7d8eefa21478c39b48174ae0efecd7 100644
--- a/Source/core/rendering/RenderFlowThread.h
+++ b/Source/core/rendering/RenderFlowThread.h
@@ -106,10 +106,6 @@ public:
         return flowThreadPoint + columnOffset(flowThreadPoint);
     }
 
-    void pushFlowThreadLayoutState(const RenderObject&);
-    void popFlowThreadLayoutState();
-    LayoutUnit offsetFromLogicalTopOfFirstRegion(const RenderBlock*) const;
-
     // Used to estimate the maximum height of the flow thread.
     static LayoutUnit maxLogicalHeight() { return LayoutUnit::max() / 2; }
 
@@ -120,12 +116,6 @@ protected:
 
     virtual RenderMultiColumnSet* columnSetAtBlockOffset(LayoutUnit) const = 0;
 
-    bool cachedOffsetFromLogicalTopOfFirstRegion(const RenderBox*, LayoutUnit&) const;
-    void setOffsetFromLogicalTopOfFirstRegion(const RenderBox*, LayoutUnit);
-    void clearOffsetFromLogicalTopOfFirstRegion(const RenderBox*);
-
-    const RenderBox* currentStatePusherRenderBox() const;
-
     RenderMultiColumnSetList m_multiColumnSetList;
 
     typedef PODInterval<LayoutUnit, RenderMultiColumnSet*> MultiColumnSetInterval;
@@ -150,13 +140,6 @@ protected:
         RenderRegion* m_result;
     };
 
-    // Stack of objects that pushed a LayoutState object on the RenderView. The
-    // objects on the stack are the ones that are curently in the process of being
-    // laid out.
-    ListHashSet<const RenderObject*> m_statePusherObjectsStack;
-    typedef HashMap<const RenderBox*, LayoutUnit> RenderBoxToOffsetMap;
-    RenderBoxToOffsetMap m_boxesToOffsetMap;
-
     MultiColumnSetIntervalTree m_multiColumnSetIntervalTree;
 
     bool m_regionsInvalidated : 1;