Be more restrictive about forcing relayout of children for pagination.

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

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2007 David Smith (catfish.man@gmail.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc.
  *               All rights reserved.
  * Copyright (C) Research In Motion Limited 2010. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ skipping 809 matching lines @@
       // TODO(cbiesinger): We could probably avoid a layout here and just
       // reposition?
       positionedObject->forceChildLayout();
       layoutChanged = true;
     }
 
     // Lay out again if our estimate was wrong.
     if (!layoutChanged && needsBlockDirectionLocationSetBeforeLayout &&
         logicalTopEstimate != logicalTopForChild(*positionedObject))
       positionedObject->forceChildLayout();
+
+    if (isPaginated)
+      updateFragmentationInfoForChild(*positionedObject);
   }
 }
 
 void LayoutBlock::markPositionedObjectsForLayout() {
   if (TrackedLayoutBoxListHashSet* positionedDescendants =
           positionedObjects()) {
     for (auto* descendant : *positionedDescendants)
       descendant->setChildNeedsLayout();
   }
 }
@@ skipping 1363 matching lines @@
   }
 
   return availableHeight;
 }
 
 bool LayoutBlock::hasDefiniteLogicalHeight() const {
   return availableLogicalHeightForPercentageComputation() != LayoutUnit(-1);
 }
 
 }  // namespace blink