Introduce NavigatorID IDL interface

Source/core/page/Navigator.h

 /*
     Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
 
     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
@@ skipping 32 matching lines @@
     static PassRefPtr<Navigator> create(Frame* frame) { return adoptRef(new Navigator(frame)); }
     virtual ~Navigator();
 
     String appVersion() const;
     String language() const;
     DOMPluginArray* plugins() const;
     DOMMimeTypeArray* mimeTypes() const;
     bool cookieEnabled() const;
     bool javaEnabled() const;
 
-    virtual String userAgent() const;
+    virtual String userAgent() const OVERRIDE;
 
     // Relinquishes the storage lock, if one exists.
     void getStorageUpdates();
 
 private:
     explicit Navigator(Frame*);
 
     mutable RefPtr<DOMPluginArray> m_plugins;
     mutable RefPtr<DOMMimeTypeArray> m_mimeTypes;
 };
 
 }
 
 #endif