Introduce adjustFloatLogicalTopForPagination(), to offload positionAndLayoutFloat().

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 801 matching lines @@
 
   void setBreakBefore(EBreak);
   void setBreakAfter(EBreak);
   EBreak breakBefore() const override;
   EBreak breakAfter() const override;
 
   LayoutUnit adjustBlockChildForPagination(LayoutUnit logicalTop,
                                            LayoutBox& child,
                                            BlockChildrenLayoutInfo&,
                                            bool atBeforeSideOfBlock);
+
+  // If a float cannot fit in the current fragmentainer, return the logical top
+  // margin edge that the float needs to have in order to be pushed to the top
+  // of the next fragmentainer. Otherwise, just return |logicalTopMarginEdge|.
+  LayoutUnit adjustFloatForPagination(LayoutBox&,
+                                      LayoutUnit logicalTopMarginEdge);
+
   // Computes a deltaOffset value that put a line at the top of the next page if
   // it doesn't fit on the current page.
   void adjustLinePositionForPagination(RootInlineBox&, LayoutUnit& deltaOffset);
+
   // If the child is unsplittable and can't fit on the current page, return the
   // top of the next page/column.
   LayoutUnit adjustForUnsplittableChild(LayoutBox&,
                                         LayoutUnit logicalOffset) const;
 
   // Used to store state between styleWillChange and styleDidChange
   static bool s_canPropagateFloatIntoSibling;
 
   LineBoxList m_lineBoxes;  // All of the root line boxes created for this block
                             // flow.  For example, <div>Hello<br>world.</div>
@@ skipping 99 matching lines @@
   void positionDialog();
 
   // END METHODS DEFINED IN LayoutBlockFlowLine
 };
 
 DEFINE_LAYOUT_OBJECT_TYPE_CASTS(LayoutBlockFlow, isLayoutBlockFlow());
 
 }  // namespace blink
 
 #endif  // LayoutBlockFlow_h