Change SelectionStartEnd() returning values instead of assigning into ref args.

third_party/WebKit/Source/core/editing/LayoutSelection.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2006 Apple Computer, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
@@ skipping 37 matching lines @@
     kPaintInvalidationNewXOROld,
     kPaintInvalidationNewMinusOld
   };
   void SetSelection(
       LayoutObject* start,
       int start_pos,
       LayoutObject*,
       int end_pos,
       SelectionPaintInvalidationMode = kPaintInvalidationNewXOROld);
   void ClearSelection();
-  void SelectionStartEnd(int& start_pos, int& end_pos);
+  std::pair<int, int> SelectionStartEnd();
   void OnDocumentShutdown();
 
   DECLARE_TRACE();
 
  private:
   LayoutSelection(FrameSelection&);
 
   const VisibleSelection& GetVisibleSelection() const;
 
   SelectionInFlatTree CalcVisibleSelection(
@@ skipping 19 matching lines @@
   // TODO(yosin): Clarify the meaning of these variables. editing/ passes
   // them as offsets in the DOM tree  but layout uses them as offset in the
   // layout tree.
   int selection_start_pos_;
   int selection_end_pos_;
 };
 
 }  // namespace blink
 
 #endif