No need to force relayout of children when page logical height changes.

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

 /*
  * 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) 2003-2013 Apple Inc. All rights reserved.
  * Copyright (C) Research In Motion Limited 2010. All rights reserved.
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
@@ skipping 572 matching lines @@
   void makeChildrenNonInline(LayoutObject* insertionPoint = nullptr);
   void childBecameNonInline(LayoutObject* child) final;
 
   void updateLogicalWidthForAlignment(const ETextAlign&,
                                       const RootInlineBox*,
                                       BidiRun* trailingSpaceRun,
                                       LayoutUnit& logicalLeft,
                                       LayoutUnit& totalLogicalWidth,
                                       LayoutUnit& availableLogicalWidth,
                                       unsigned expansionOpportunityCount);
-  void checkForPaginationLogicalHeightChange(
-      LayoutUnit& pageLogicalHeight,
-      bool& pageLogicalHeightChanged,
-      bool& hasSpecifiedPageLogicalHeight);
+  void checkForPaginationLogicalHeightChange(LayoutUnit& pageLogicalHeight);
 
   bool shouldBreakAtLineToAvoidWidow() const {
     return m_rareData && m_rareData->m_lineBreakToAvoidWidow >= 0;
   }
   void clearShouldBreakAtLineToAvoidWidow() const;
   int lineBreakToAvoidWidow() const {
     return m_rareData ? m_rareData->m_lineBreakToAvoidWidow : -1;
   }
   void setBreakAtLineToAvoidWidow(int);
   void clearDidBreakAtLineToAvoidWidow();
@@ skipping 337 matching lines @@
   void positionDialog();
 
   // END METHODS DEFINED IN LayoutBlockFlowLine
 };
 
 DEFINE_LAYOUT_OBJECT_TYPE_CASTS(LayoutBlockFlow, isLayoutBlockFlow());
 
 }  // namespace blink
 
 #endif  // LayoutBlockFlow_h