Include overflow when setting the logical flowthread bottom on the last column set.

Source/core/layout/MultiColumnFragmentainerGroup.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MultiColumnFragmentainerGroup_h
 #define MultiColumnFragmentainerGroup_h
 
 #include "core/layout/LayoutMultiColumnFlowThread.h"
 
 namespace blink {
@@ skipping 38 matching lines @@
     // The height of our flow thread portion
     LayoutUnit logicalHeightInFlowThread() const { return m_logicalBottomInFlowThread - m_logicalTopInFlowThread; }
 
     bool heightIsAuto() const;
     void resetColumnHeight();
     void addContentRun(LayoutUnit endOffsetInFlowThread);
     void updateMinimumColumnHeight(LayoutUnit height) { m_minimumColumnHeight = std::max(height, m_minimumColumnHeight); }
     void recordSpaceShortage(LayoutUnit);
     bool recalculateColumnHeight(BalancedColumnHeightCalculation calculationMode);
 
-    void expandToEncompassFlowThreadOverflow();
-
     LayoutSize flowThreadTranslationAtOffset(LayoutUnit offsetInFlowThread) const;
     LayoutUnit columnLogicalTopForOffset(LayoutUnit offsetInFlowThread) const;
     LayoutPoint visualPointToFlowThreadPoint(const LayoutPoint& visualPoint) const;
     void collectLayerFragments(DeprecatedPaintLayerFragments&, const LayoutRect& layerBoundingBox, const LayoutRect& dirtyRect) const;
     LayoutRect calculateOverflow() const;
 
     // The "CSS actual" value of column-count. This includes overflowing columns, if any.
     unsigned actualColumnCount() const;
 
 private:
@@ skipping 105 matching lines @@
 
 private:
     LayoutMultiColumnSet& m_columnSet;
 
     Vector<MultiColumnFragmentainerGroup, 1> m_groups;
 };
 
 } // namespace blink
 
 #endif // MultiColumnFragmentainerGroup_h