code: function listen(name, callBack) {
    function f() {
      try {
        callBack.apply(this, arguments);
      } catch (e) {
        console.error(e); // eslint-disable-line no-console
      }
    }
    callbacks[callBack] = f;
    messageBus.bind(name, f);
  }
docs: Registers a listener of the specified message. Whenever the specified
  message is sent, the specified callBack function will be invoked passing
  the parameters specified in the send invocation
  
  @param {string}
  name - The name of the message.
  @param {function}
  callBack - A function receiving (a) an "event" object and (b)
  the sequence of parameters specified in the call to send.
  @return {undefined}