Distinguish between row (fragmentainer group) height and column (fragmentainer) height.

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

 /*
  * 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 655 matching lines @@
         // additional rows in ancestral multicol containers before doing it in
         // the descendants, in order to get the height constraints right down
         // there.
         const MultiColumnFragmentainerGroup& last_row =
             column_set->LastFragmentainerGroup();
         // The top offset where where the new fragmentainer group will start in
         // this column set, converted to the coordinate space of the enclosing
         // multicol container.
         LayoutUnit logical_offset_in_outer =
             last_row.BlockOffsetInEnclosingFragmentationContext() +
-            last_row.LogicalHeight();
+            last_row.GroupLogicalHeight();
         enclosing_flow_thread->AppendNewFragmentainerGroupIfNeeded(
             logical_offset_in_outer, kAssociateWithLatterPage);
       }
 
       const MultiColumnFragmentainerGroup& new_row =
           column_set->AppendNewFragmentainerGroup();
       // Zero-height rows should really not occur here, but if it does anyway,
       // break, so that we don't get stuck in an infinite loop.
-      DCHECK_GT(new_row.LogicalHeight(), 0);
-      if (new_row.LogicalHeight() <= 0)
+      DCHECK_GT(new_row.ColumnLogicalHeight(), 0);
+      if (new_row.ColumnLogicalHeight() <= 0)
         break;
     } while (column_set->NeedsNewFragmentainerGroupAt(offset_in_flow_thread,
                                                       page_boundary_rule));
   }
 }
 
 bool LayoutMultiColumnFlowThread::IsFragmentainerLogicalHeightKnown() {
   return IsPageLogicalHeightKnown();
 }
 
@@ skipping 714 matching lines @@
     const {
   return MultiColumnLayoutState(last_set_worked_on_);
 }
 
 void LayoutMultiColumnFlowThread::RestoreMultiColumnLayoutState(
     const MultiColumnLayoutState& state) {
   last_set_worked_on_ = state.ColumnSet();
 }
 
 }  // namespace blink