getAttachedPseudoElements() {
    let ordered = {};
    let that = this;
    Object.keys(this.attachedPseudoElements).sort().forEach(function (key) {
      ordered[key] = that.attachedPseudoElements[key];
    });
    return ordered;
  }
Returns the attached pseudo elements sorted by hydrogen count (ascending).

@returns {Object} The sorted attached pseudo elements.