Introduce nextPositionOf() for VisiblePosition

Source/core/editing/Editor.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
  *
  * 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 1005 matching lines @@
 {
     if (!canEdit())
         return;
 
     VisibleSelection selection = frame().selection().selection();
     if (!selection.isCaret())
         return;
 
     // Make a selection that goes back one character and forward two characters.
     VisiblePosition caret = selection.visibleStart();
-    VisiblePosition next = isEndOfParagraph(caret) ? caret : caret.next();
+    VisiblePosition next = isEndOfParagraph(caret) ? caret : nextPositionOf(caret);
     VisiblePosition previous = previousPositionOf(next);
     if (next.deepEquivalent() == previous.deepEquivalent())
         return;
     previous = previousPositionOf(previous);
     if (!inSameParagraph(next, previous))
         return;
     const EphemeralRange range = makeRange(previous, next);
     if (range.isNull())
         return;
     VisibleSelection newSelection(range);
@@ skipping 264 matching lines @@
 }
 
 DEFINE_TRACE(Editor)
 {
     visitor->trace(m_frame);
     visitor->trace(m_lastEditCommand);
     visitor->trace(m_mark);
 }
 
 } // namespace blink