Remove the old multicol implementation.

Source/core/layout/LayoutBlockFlow.h

Index: Source/core/layout/LayoutBlockFlow.h
diff --git a/Source/core/layout/LayoutBlockFlow.h b/Source/core/layout/LayoutBlockFlow.h
index f9333810f8f5557d0066ec3fb08dbb1efa50b50d..5c2db784c58c6adbe870c260f9dbe196c961b9a1 100644
--- a/Source/core/layout/LayoutBlockFlow.h
+++ b/Source/core/layout/LayoutBlockFlow.h
@@ -288,7 +288,7 @@ private:
 
     LayoutUnit getClearDelta(LayoutBox* child, LayoutUnit yPos);
 
-    bool hasOverhangingFloats() { return parent() && !hasColumns() && containsFloats() && lowestFloatLogicalBottom() > logicalHeight(); }
+    bool hasOverhangingFloats() { return parent() && containsFloats() && lowestFloatLogicalBottom() > logicalHeight(); }
     bool hasOverhangingFloat(LayoutBox*);
     void addIntrudingFloats(LayoutBlockFlow* prev, LayoutUnit xoffset, LayoutUnit yoffset);
     void addOverhangingFloats(LayoutBlockFlow* child, bool makeChildPaintOtherFloats);
@@ -331,8 +331,6 @@ private:
 
     void updateLogicalWidthForAlignment(const ETextAlign&, const RootInlineBox*, BidiRun* trailingSpaceRun, LayoutUnit& logicalLeft, LayoutUnit& totalLogicalWidth, LayoutUnit& availableLogicalWidth, unsigned expansionOpportunityCount);
     void checkForPaginationLogicalHeightChange(LayoutUnit& pageLogicalHeight, bool& pageLogicalHeightChanged, bool& hasSpecifiedPageLogicalHeight);
-    bool shouldRelayoutForPagination(LayoutUnit& pageLogicalHeight, LayoutUnit layoutOverflowLogicalBottom) const;
-    void setColumnCountAndHeight(unsigned count, LayoutUnit pageLogicalHeight);
 
     bool shouldBreakAtLineToAvoidWidow() const { return m_rareData && m_rareData->m_lineBreakToAvoidWidow >= 0; }
     void clearShouldBreakAtLineToAvoidWidow() const;