Column balancing refactoring. Don't propagate data during layout.

third_party/WebKit/Source/core/layout/LayoutMultiColumnSet.h

 /*
  * Copyright (C) 2012 Apple Inc.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 95 matching lines @@
     bool heightIsAuto() const;
 
     // Find the column that contains the given block offset, and return the translation needed to
     // get from flow thread coordinates to visual coordinates.
     LayoutSize flowThreadTranslationAtOffset(LayoutUnit) const;
 
     LayoutPoint visualPointToFlowThreadPoint(const LayoutPoint& visualPoint) const;
 
     void updateMinimumColumnHeight(LayoutUnit offsetInFlowThread, LayoutUnit height);
 
-    // Add a content run, specified by its end position. A content run is appended at every
-    // forced/explicit break and at the end of the column set. The content runs are used to
-    // determine where implicit/soft breaks will occur, in order to calculate an initial column
-    // height.
-    void addContentRun(LayoutUnit endOffsetFromFirstPage);
-
     // (Re-)calculate the column height if it's auto. This is first and foremost needed by sets that
     // are to balance the column height, but even when it isn't to be balanced, this is necessary if
     // the multicol container's height is constrained.
     bool recalculateColumnHeight(BalancedColumnHeightCalculation);
 
-    // Record space shortage (the amount of space that would have been enough to prevent some
-    // element from being moved to the next column) at a column break. The smallest amount of space
-    // shortage we find is the amount with which we will stretch the column height, if it turns out
-    // after layout that the columns weren't tall enough.
-    void recordSpaceShortage(LayoutUnit offsetInFlowThread, LayoutUnit);
-
     // Reset previously calculated column height. Will mark for layout if needed.
     void resetColumnHeight();
 
     // Layout of flow thread content that's to be rendered inside this column set begins. This
     // happens at the beginning of flow thread layout, and when advancing from a previous column set
     // or spanner to this one.
     void beginFlow(LayoutUnit offsetInFlowThread);
 
     // Layout of flow thread content that was to be rendered inside this column set has
     // finished. This happens at end of flow thread layout, and when advancing to the next column
@@ skipping 40 matching lines @@
     MultiColumnFragmentainerGroupList m_fragmentainerGroups;
     LayoutFlowThread* m_flowThread;
 };
 
 DEFINE_LAYOUT_OBJECT_TYPE_CASTS(LayoutMultiColumnSet, isLayoutMultiColumnSet());
 
 } // namespace blink
 
 #endif // LayoutMultiColumnSet_h