Remove SetWrapperReferenceTo and SetWrapperReferenceFrom

third_party/WebKit/Source/core/html/track/TrackBase.cpp

 /*
  * Copyright (C) 2013 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 30 matching lines @@
                      const String& id)
     : m_type(type),
       m_kind(kind),
       m_label(label),
       m_language(language),
       m_id(id),
       m_mediaElement(nullptr) {}
 
 TrackBase::~TrackBase() {}
 
-Node* TrackBase::owner() const {
-  return m_mediaElement;
-}
-
 DEFINE_TRACE(TrackBase) {
   Supplementable<TrackBase>::trace(visitor);
   visitor->trace(m_mediaElement);
 }
 
 }  // namespace blink