Make MultiColumnFragmentainerGroup::m_columnSet const.

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 "core/layout/MultiColumnFragmentainerGroup.h"
 
 #include "core/layout/ColumnBalancer.h"
 #include "core/layout/FragmentationContext.h"
 #include "core/layout/LayoutMultiColumnSet.h"
 
 namespace blink {
 
-MultiColumnFragmentainerGroup::MultiColumnFragmentainerGroup(LayoutMultiColumnSet& columnSet)
+MultiColumnFragmentainerGroup::MultiColumnFragmentainerGroup(const LayoutMultiColumnSet& columnSet)
     : m_columnSet(columnSet)
 {
 }
 
 bool MultiColumnFragmentainerGroup::isFirstGroup() const
 {
     return &m_columnSet.firstFragmentainerGroup() == this;
 }
 
 bool MultiColumnFragmentainerGroup::isLastGroup() const
@@ skipping 26 matching lines @@
             // this MultiColumnFragmentainerGroup can hold, and when we need to append a new one.
             m_columnHeight = m_maxColumnHeight;
         } else {
             m_columnHeight = LayoutUnit();
         }
     } else {
         setAndConstrainColumnHeight(heightAdjustedForRowOffset(flowThread->columnHeightAvailable()));
     }
 }
 
-bool MultiColumnFragmentainerGroup::recalculateColumnHeight()
+bool MultiColumnFragmentainerGroup::recalculateColumnHeight(LayoutMultiColumnSet& columnSet)
 {
     LayoutUnit oldColumnHeight = m_columnHeight;
 
     m_maxColumnHeight = calculateMaxColumnHeight();
 
     // 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.
-    if (isLastGroup() && m_columnSet.heightIsAuto()) {
+    if (isLastGroup() && columnSet.heightIsAuto()) {
         LayoutUnit newColumnHeight;
-        if (!m_columnSet.isInitialHeightCalculated()) {
+        if (!columnSet.isInitialHeightCalculated()) {
             // Initial balancing: Start with the lowest imaginable column height. Also calculate the
             // height of the tallest piece of unbreakable content. Columns should never get any
             // shorter than that (unless constrained by max-height). Propagate this to our
             // containing column set, in case there is an outer multicol container that also needs
             // to balance. After having calculated the initial column height, the multicol container
             // needs another layout pass with the column height that we just calculated.
-            InitialColumnHeightFinder initialHeightFinder(columnSet(), logicalTopInFlowThread(), logicalBottomInFlowThread());
+            InitialColumnHeightFinder initialHeightFinder(columnSet, logicalTopInFlowThread(), logicalBottomInFlowThread());
             LayoutUnit tallestUnbreakableLogicalHeight = initialHeightFinder.tallestUnbreakableLogicalHeight();
-            m_columnSet.propagateTallestUnbreakableLogicalHeight(tallestUnbreakableLogicalHeight);
+            columnSet.propagateTallestUnbreakableLogicalHeight(tallestUnbreakableLogicalHeight);
             newColumnHeight = std::max(initialHeightFinder.initialMinimalBalancedHeight(), tallestUnbreakableLogicalHeight);
         } else {
             // Rebalancing: After having laid out again, we'll need to rebalance if the height
             // wasn't enough and we're allowed to stretch it, and then re-lay out. There are further
             // details on the column balancing machinery in ColumnBalancer and its derivates.
             newColumnHeight = rebalanceColumnHeightIfNeeded();
         }
         setAndConstrainColumnHeight(newColumnHeight);
     } else {
         // The position of the column set may have changed, in which case height available for
@@ skipping 441 matching lines @@
     append(MultiColumnFragmentainerGroup(m_columnSet));
     return last();
 }
 
 void MultiColumnFragmentainerGroupList::deleteExtraGroups()
 {
     shrink(1);
 }
 
 } // namespace blink