function computeDurationText(durationTime) {
    var durationText = "00:00";

    if (!isNaN(durationTime.minutes) && !isNaN(durationTime.seconds)) {
      durationText = durationTime.minutes + ":" + durationTime.seconds;
      if (!isNaN(durationTime.hours) && durationTime.hours > 0) {
        durationText = durationTime.hours + ":" + durationText;
      }
    }

    return durationText;
  }
Computes the duration text

@param {Object} durationTime - An object containint the duration times.