Calculate minimum column height after layout.

third_party/WebKit/Source/core/layout/MultiColumnFragmentainerGroup.cpp

 // 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.
 
 #include "config.h"
 
 #include "core/layout/MultiColumnFragmentainerGroup.h"
 
 #include "core/layout/ColumnBalancer.h"
 #include "core/layout/LayoutMultiColumnSet.h"
@@ skipping 31 matching lines @@
 bool MultiColumnFragmentainerGroup::heightIsAuto() const
 {
     // Only the last row may have auto height, and thus be balanced. There are no good reasons to
     // balance the preceding rows, and that could potentially lead to an insane number of layout
     // passes as well.
     return isLastGroup() && m_columnSet.heightIsAuto();
 }
 
 void MultiColumnFragmentainerGroup::resetColumnHeight()
 {
-    // Nuke previously stored minimum column height. Contents may have changed for all we know.
-    m_minimumColumnHeight = 0;
-
     m_maxColumnHeight = calculateMaxColumnHeight();
 
     LayoutMultiColumnFlowThread* flowThread = m_columnSet.multiColumnFlowThread();
     if (heightIsAuto()) {
         LayoutMultiColumnFlowThread* enclosingFlowThread = flowThread->enclosingFlowThread();
         if (enclosingFlowThread && enclosingFlowThread->isPageLogicalHeightKnown()) {
             // Even if height is auto, we set an initial height, in order to tell how much content
             // this MultiColumnFragmentainerGroup can hold, and when we need to append a new one.
             m_columnHeight = m_maxColumnHeight;
         } else {
@@ skipping 274 matching lines @@
         m_columnHeight = m_maxColumnHeight;
 }
 
 LayoutUnit MultiColumnFragmentainerGroup::calculateColumnHeight(BalancedColumnHeightCalculation calculationMode) const
 {
     if (calculationMode == GuessFromFlowThreadPortion) {
         // Initial balancing. Start with the lowest imaginable column height. We use the tallest
         // content run (after having "inserted" implicit breaks), and find its start offset (by
         // looking at the previous run's end offset, or, if there's no previous run, the set's start
         // offset in the flow thread).
-        return std::max(InitialColumnHeightFinder::initialMinimalBalancedHeight(*this), m_minimumColumnHeight);
+        return InitialColumnHeightFinder::initialMinimalBalancedHeight(*this);
     }
 
     if (actualColumnCount() <= m_columnSet.usedColumnCount()) {
         // With the current column height, the content fits without creating overflowing columns. We're done.
         return m_columnHeight;
     }
 
     if (m_columnHeight >= m_maxColumnHeight) {
         // We cannot stretch any further. We'll just have to live with the overflowing columns. This
         // typically happens if the max column height is less than the height of the tallest piece
@@ skipping 197 matching lines @@
     append(MultiColumnFragmentainerGroup(m_columnSet));
     return last();
 }
 
 void MultiColumnFragmentainerGroupList::deleteExtraGroups()
 {
     shrink(1);
 }
 
 } // namespace blink