code: function setMessage(state, message) {
    Object.defineProperty(state, 'message', {value: message, writable: true, configurable: true, enumerable: false});
  }
docs: ===================================================================================================================== Tracked state-related utilities ===================================================================================================================== 
  Sets the given message on its given state that is being tracked for the message.
  @param {MessageState} state - the tracked state to be updated
  @param {Message} message - the message to which this state belongs