src/libs/Bus.js
function subscribeTo(sChannelId, sEventType, fpHandler, oSubscriber) {
  const aChannelEvents = _getChannelEvents(sChannelId, sEventType);
  aChannelEvents.push({
    subscriber: oSubscriber,
    handler: fpHandler
  });
}
function subscribeTo(sChannelId, sEventType, fpHandler, oSubscriber) {
  const aChannelEvents = _getChannelEvents(sChannelId, sEventType);
  aChannelEvents.push({
    subscriber: oSubscriber,
    handler: fpHandler
  });
}
Method to add a single callback in one channel an in one event.
@param {String} sChannelId
@param {String} sEventType
@param {Function} fpHandler
@param {Object} oSubscriber