Need a deep layout pass when becoming (un)fragmented.

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

 /*
  * Copyright (C) 2007 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 19 matching lines @@
 #include "core/layout/LayoutView.h"
 
 namespace blink {
 
 LayoutState::LayoutState(LayoutUnit pageLogicalHeight,
                          bool pageLogicalHeightChanged,
                          LayoutView& view)
     : m_isPaginated(pageLogicalHeight),
       m_pageLogicalHeightChanged(pageLogicalHeightChanged),
       m_containingBlockLogicalWidthChanged(false),
+      m_paginationStateChanged(false),
       m_flowThread(nullptr),
       m_next(nullptr),
       m_pageLogicalHeight(pageLogicalHeight),
       m_layoutObject(view) {
   ASSERT(!view.layoutState());
   view.pushLayoutState(*this);
 }
 
 LayoutState::LayoutState(LayoutBox& layoutObject,
                          const LayoutSize& offset,
                          LayoutUnit pageLogicalHeight,
                          bool pageLogicalHeightChanged,
                          bool containingBlockLogicalWidthChanged)
     : m_containingBlockLogicalWidthChanged(containingBlockLogicalWidthChanged),
       m_next(layoutObject.view()->layoutState()),
       m_layoutObject(layoutObject) {
   if (layoutObject.isLayoutFlowThread())
     m_flowThread = toLayoutFlowThread(&layoutObject);
   else if (!layoutObject.isOutOfFlowPositioned())
     m_flowThread = m_next->flowThread();
   else
     m_flowThread = nullptr;
+  m_paginationStateChanged = m_next->m_paginationStateChanged;
   layoutObject.view()->pushLayoutState(*this);
   bool fixed = layoutObject.isOutOfFlowPositioned() &&
                layoutObject.style()->position() == FixedPosition;
   if (fixed) {
     // FIXME: This doesn't work correctly with transforms.
     FloatPoint fixedOffset =
         layoutObject.view()->localToAbsolute(FloatPoint(), IsFixed);
     m_layoutOffset = LayoutSize(fixedOffset.x(), fixedOffset.y()) + offset;
   } else {
     m_layoutOffset = m_next->m_layoutOffset + offset;
@@ skipping 50 matching lines @@
   }
 
   // FIXME: <http://bugs.webkit.org/show_bug.cgi?id=13443> Apply control clip if
   // present.
 }
 
 LayoutState::LayoutState(LayoutObject& root)
     : m_isPaginated(false),
       m_pageLogicalHeightChanged(false),
       m_containingBlockLogicalWidthChanged(false),
+      m_paginationStateChanged(false),
       m_flowThread(nullptr),
       m_next(root.view()->layoutState()),
       m_layoutObject(root) {
   ASSERT(!m_next);
   // We'll end up pushing in LayoutView itself, so don't bother adding it.
   if (root.isLayoutView())
     return;
 
   root.view()->pushLayoutState(*this);
 
@@ skipping 12 matching lines @@
 
 LayoutUnit LayoutState::pageLogicalOffset(
     const LayoutBox& child,
     const LayoutUnit& childLogicalOffset) const {
   if (child.isHorizontalWritingMode())
     return m_layoutOffset.height() + childLogicalOffset - m_pageOffset.height();
   return m_layoutOffset.width() + childLogicalOffset - m_pageOffset.width();
 }
 
 }  // namespace blink