anchor.diff:  
   class Atom extends ProxyHolder {
     CommandRegistry _commands;
  -  // Config _config;
  +  Config _config;
     // ContextMenuManager _contextMenu;
     // GrammarRegistry _grammars;
     NotificationManager _notifications;
  
positive.code:   /// Simulate the dispatch of a command on a DOM node.
    void dispatch(Element target, String commandName, {Map options}) =>
        invoke('dispatch', target, commandName, options);
  }
  
  /// A notification manager used to create notifications to be shown to the user.
  
negative.code:   }
  
    CommandRegistry get commands => _commands;
    Config get config => _config;
    // ContextMenuManager get contextMenu => _contextMenu;
    // GrammarRegistry get grammars => _grammars;
    NotificationManager get notifications => _notifications;
  