Remove the Notation interface

Source/core/dom/Notation.h

-/*
- * Copyright (C) 2000 Peter Kelly (pmk@post.com)
- * Copyright (C) 2006, 2009 Apple Inc. All rights reserved.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Library General Public
- * License as published by the Free Software Foundation; either
- * version 2 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Library General Public License for more details.
- *
- * You should have received a copy of the GNU Library General Public License
- * along with this library; see the file COPYING.LIB.  If not, write to
- * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
- * Boston, MA 02110-1301, USA.
- *
- */
-
-#ifndef Notation_h
-#define Notation_h
-
-#include "core/dom/ContainerNode.h"
-
-namespace blink {
-
-class Notation : public ContainerNode {
-private:
-    Notation(); // Left unimplemented on purpose.
-};
-
-} // namespace blink
-
-#endif