code: function calculateShow(availability) {
    var show = new TimeIntervalCollectionProperty();
    if (!defined(availability) || !defined(availability.start)) {
      show.intervals.addInterval(
        new TimeInterval({
          start: Iso8601.MINIMUM_VALUE,
          stop: Iso8601.MAXIMUM_VALUE,
          data: true
        })
      );
    } else {
      var start = availability.start;
      var stop = availability.stop;
      show.intervals.addInterval(
        new TimeInterval({
          start: Iso8601.MINIMUM_VALUE,
          stop: Iso8601.MAXIMUM_VALUE,
          data: false
        })
      );
      show.intervals.addInterval(
        new TimeInterval({ start: start, stop: stop, data: true })
      );
    }
    return show;
  }
docs: Calculate the "show" interval collection property, given the availability.
  The show property has data=true/false over the period it is visible/invisible.
  If availability is undefined, it has data=false over all possible time.
  @private
  @param  {TimeIntervalCollection} [availability] The availability interval, used to get the start and stop dates. Only the first interval in the collection is used.
  @return {TimeIntervalCollectionProperty} Has data=false/true over the period this entry is invisible/visible (even if timeColumn is undefined).