Introduce resetLayout(), to offload layoutBlockFlow().

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 458 matching lines @@
 
   Node* nodeForHitTest() const final;
   bool hitTestChildren(HitTestResult&,
                        const HitTestLocation& locationInContainer,
                        const LayoutPoint& accumulatedOffset,
                        HitTestAction) override;
 
   LayoutSize accumulateInFlowPositionOffsets() const override;
 
  private:
+  void resetLayout();
   bool layoutBlockFlow(bool relayoutChildren,
                        SubtreeLayoutScope&);
   void addOverhangingFloatsFromChildren(LayoutUnit unconstrainedHeight);
   void layoutBlockChildren(bool relayoutChildren,
                            SubtreeLayoutScope&,
                            LayoutUnit beforeEdge,
                            LayoutUnit afterEdge);
 
   void markDescendantsWithFloatsForLayoutIfNeeded(
       LayoutBlockFlow& child,
@@ skipping 450 matching lines @@
   void positionDialog();
 
   // END METHODS DEFINED IN LayoutBlockFlowLine
 };
 
 DEFINE_LAYOUT_OBJECT_TYPE_CASTS(LayoutBlockFlow, isLayoutBlockFlow());
 
 }  // namespace blink
 
 #endif  // LayoutBlockFlow_h