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

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

 /*
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010 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
@@ skipping 235 matching lines @@
   void UpdateAppearance(LayoutSelection::PaintHint);
   bool ShouldShowBlockCursor() const;
   void SetShouldShowBlockCursor(bool);
 
   void CacheRangeOfDocument(Range*);
   Range* DocumentCachedRange() const;
   void ClearDocumentCachedRange();
 
   FrameCaret& FrameCaretForTesting() const { return *frame_caret_; }
 
-  void LayoutSelectionStartEnd(int& start_pos, int& end_pos);
+  std::pair<int, int> LayoutSelectionStartEnd();
   void ClearLayoutSelection();
 
   DECLARE_TRACE();
 
  private:
   friend class CaretDisplayItemClientTest;
   friend class FrameSelectionTest;
   friend class PaintControllerPaintTestForSlimmingPaintV1AndV2;
   friend class SelectionControllerTest;
   FRIEND_TEST_ALL_PREFIXES(PaintControllerPaintTestForSlimmingPaintV1AndV2,
@@ skipping 47 matching lines @@
 
 }  // namespace blink
 
 #ifndef NDEBUG
 // Outside the WebCore namespace for ease of invocation from gdb.
 void showTree(const blink::FrameSelection&);
 void showTree(const blink::FrameSelection*);
 #endif
 
 #endif  // FrameSelection_h