// Seems weird
  protected function getDiscovery() {
    if (!isset($this->discovery)) {
      $this->discovery = new HookDiscovery('aggregator_fetch_info');
    }
    return $this->discovery;
  }
// Seems less weird
  protected function getDiscovery() {
    if (!isset($this->discovery)) {
      return parent::getDiscovery();
    }
    return $this->discovery;
  }