discoverAddonAddons() {
    let addonPackageList = [];

    this.addPackages(
      addonPackageList,
      this.dependencyPackages,
      (pkgInfo) => !pkgInfo.isForAddon() || pkgInfo.name === 'ember-cli'
    );
    this.addPackages(addonPackageList, this.inRepoAddons);

    return addonPackageList;
  }
Discover the child addons for this packageInfo, which corresponds to an Addon.

@method discoverAddonAddons