function CurveTimeline2(frameCount, bezierCount, propertyId1, propertyId2) {
    return _super.call(this, frameCount, bezierCount, [propertyId1, propertyId2]) || this;
  }
@param bezierCount The maximum number of Bezier curves. See {@link #shrink(int)}.
@param propertyIds Unique identifiers for the properties the timeline modifies.