function PolygonHierarchy(positions, holes) {
  /**
   * A linear ring defining the outer boundary of the polygon or hole.
   * @type {Cartesian3[]}
   */
  this.positions = defined(positions) ? positions : [];

  /**
   * An array of polygon hierarchies defining holes in the polygon.
   * @type {PolygonHierarchy[]}
   */
  this.holes = defined(holes) ? holes : [];
}
An hierarchy of linear rings which define a polygon and its holes.
The holes themselves may also have holes which nest inner polygons.
@alias PolygonHierarchy
@constructor

@param {Cartesian3[]} [positions] A linear ring defining the outer boundary of the polygon or hole.
@param {PolygonHierarchy[]} [holes] An array of polygon hierarchies defining holes in the polygon.