Introduce fragmentainerGroupCapacity().

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 89 matching lines @@
     bool hasFragmentainerGroupForColumnAt(LayoutUnit bottomOffsetInFlowThread, PageBoundaryRule) const;
 
     MultiColumnFragmentainerGroup& appendNewFragmentainerGroup();
 
     // Logical top relative to the content edge of the multicol container.
     LayoutUnit logicalTopFromMulticolContentEdge() const;
 
     LayoutUnit logicalTopInFlowThread() const;
     LayoutUnit logicalBottomInFlowThread() const;
     LayoutUnit logicalHeightInFlowThread() const { return logicalBottomInFlowThread() - logicalTopInFlowThread(); }
+
+    // Return the amount of flow thread contents that the specified fragmentainer group can hold
+    // without overflowing.
+    LayoutUnit fragmentainerGroupCapacity(const MultiColumnFragmentainerGroup &group) const { return group.logicalHeight() * usedColumnCount(); }
+
     LayoutRect flowThreadPortionRect() const;
     LayoutRect flowThreadPortionOverflowRect() const;
     LayoutRect overflowRectForFlowThreadPortion(const LayoutRect& flowThreadPortionRect, bool isFirstPortion, bool isLastPortion) const;
 
     // The used CSS value of column-count, i.e. how many columns there are room for without overflowing.
     unsigned usedColumnCount() const { return multiColumnFlowThread()->columnCount(); }
 
     bool heightIsAuto() const;
 
     // Find the column that contains the given block offset, and return the translation needed to
@@ skipping 78 matching lines @@
 
     bool m_initialHeightCalculated;
 };
 
 DEFINE_LAYOUT_OBJECT_TYPE_CASTS(LayoutMultiColumnSet, isLayoutMultiColumnSet());
 
 } // namespace blink
 
 #endif // LayoutMultiColumnSet_h