src/libs/Bus.js
function unsubscribeFrom(sChannelId, sEventType, oSubscriber) {
  const aChannelEvents = _getChannelEvents(sChannelId, sEventType);
  for (let nEvent = aChannelEvents.length - 1; nEvent >= 0; nEvent--) {
    const oItem = aChannelEvents[nEvent];
    if (oItem.subscriber === oSubscriber) {
      aChannelEvents.splice(nEvent, 1);
    }
  }
}
function unsubscribeFrom(sChannelId, sEventType, oSubscriber) {
  const aChannelEvents = _getChannelEvents(sChannelId, sEventType);
  for (let nEvent = aChannelEvents.length - 1; nEvent >= 0; nEvent--) {
    const oItem = aChannelEvents[nEvent];
    if (oItem.subscriber === oSubscriber) {
      aChannelEvents.splice(nEvent, 1);
    }
  }
}
Method to unsubscribe a subscriber from a channel and event type.
It iterates in reverse order to avoid messing with array length when removing items.
@param {String} sChannelId
@param {String} sEventType
@param {Object} oSubscriber