[Editing][DOM][CodeHealth] Move Node::*editable* functions to core/editing

third_party/WebKit/Source/core/editing/commands/MergeIdenticalElementsCommand.cpp

 /*
  * Copyright (C) 2005, 2008 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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 10 matching lines @@
  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "core/editing/commands/MergeIdenticalElementsCommand.h"
 
 #include "bindings/core/v8/ExceptionState.h"
 #include "bindings/core/v8/ExceptionStatePlaceholder.h"
 #include "core/dom/Element.h"
+#include "core/editing/EditingUtilities.h"
 
 namespace blink {
 
 MergeIdenticalElementsCommand::MergeIdenticalElementsCommand(Element* first, Element* second)
     : SimpleEditCommand(first->document())
     , m_element1(first)
     , m_element2(second)
 {
     DCHECK(m_element1);
     DCHECK(m_element2);
@@ skipping 43 matching lines @@
 
 DEFINE_TRACE(MergeIdenticalElementsCommand)
 {
     visitor->trace(m_element1);
     visitor->trace(m_element2);
     visitor->trace(m_atChild);
     SimpleEditCommand::trace(visitor);
 }
 
 } // namespace blink