Prefer lengthOfContents over countChildren

Source/core/editing/DOMSelection.cpp

 /*
  * Copyright (C) 2007, 2009 Apple Inc. All rights reserved.
  * Copyright (C) 2012 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 met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
@@ skipping 326 matching lines @@
 {
     ASSERT(node);
 
     if (!m_frame)
         return;
 
     if (offset < 0) {
         exceptionState.throwDOMException(IndexSizeError, String::number(offset) + " is not a valid offset.");
         return;
     }
-    if (static_cast<unsigned>(offset) > (node->offsetInCharacters() ? node->lengthOfContents() : node->countChildren())) {
+    if (static_cast<unsigned>(offset) > node->lengthOfContents()) {
         exceptionState.throwDOMException(IndexSizeError, String::number(offset) + " is larger than the given node's length.");
         return;
     }
 
     if (!isValidForPosition(node))
         return;
 
     // FIXME: Eliminate legacy editing positions
     m_frame->selection().setExtent(VisiblePosition(createLegacyEditingPosition(node, offset), DOWNSTREAM));
 }
@@ skipping 202 matching lines @@
         m_treeScope->document().addConsoleMessage(ConsoleMessage::create(JSMessageSource, ErrorMessageLevel, message));
 }
 
 void DOMSelection::trace(Visitor* visitor)
 {
     visitor->trace(m_treeScope);
     DOMWindowProperty::trace(visitor);
 }
 
 } // namespace blink