Calculate minimum column height after layout.

third_party/WebKit/Source/core/layout/ColumnBalancer.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.
 
 #include "core/layout/MultiColumnFragmentainerGroup.h"
 
 namespace blink {
 
 // A column balancer traverses the portion of the subtree of a flow thread that belongs to a given
 // fragmentainer group, in order to collect certain data to be used for column balancing. This is an
@@ skipping 120 matching lines @@
     // so on). There may be several objects that cross the same column boundary, and we're only
     // interested in the shortest one. For example, when having a float beside regular in-flow
     // content, we end up with two parallel fragmentation flows [1]. The shortest strut found at a
     // column boundary is the amount of space that we wasted at said column boundary, and it needs
     // to be deducted when estimating the initial balanced column height, or we risk making the
     // column row too tall. An entry set to LayoutUnit::max() means that we didn't detect any object
     // crossing that boundary.
     //
     // [1] http://www.w3.org/TR/css3-break/#parallel-flows
     Vector<LayoutUnit, 32> m_shortestStruts;
+
+    LayoutUnit m_minimumColumnLogicalHeight;
 };
 
 // If we have previously used InitialColumnHeightFinder to estimate an initial column height, and
 // that didn't result in tall enough columns, we need subsequent layout passes where we increase
 // the column height by the minimum space shortage at column breaks. This class finds the minimum
 // space shortage after having laid out with the current column height.
 class MinimumSpaceShortageFinder final : public ColumnBalancer {
 public:
     MinimumSpaceShortageFinder(const MultiColumnFragmentainerGroup&);
 
@@ skipping 18 matching lines @@
     LayoutUnit m_minimumSpaceShortage;
 
     // Set when breaking before a block, and we're looking for the first unbreakable descendant, in
     // order to report correct space shortage for that one.
     LayoutUnit m_pendingStrut;
 
     unsigned m_forcedBreaksCount;
 };
 
 } // namespace blink