class ExtensionInstallStorage

class ExtensionInstallStorage extends InstallStorage {

  /**
   * The active configuration store.
   *
   * @var \Drupal\Core\Config\StorageInterface
   */
  protected $configStorage;

  /**
   * Flag to include the profile in the list of enabled modules.
   *
   * @var bool
   */
  protected $includeProfile = TRUE;

  /**
   * The name of the currently active installation profile.
   *
   * In the early installer this value can be NULL.
   *
   * @var string|false|null
   */
  protected $installProfile;

  /**
   * Overrides \Drupal\Core\Config\InstallStorage::__construct().
   *
   * @param \Drupal\Core\Config\StorageInterface $config_storage
   *   The active configuration store where the list of enabled modules and
   *   themes is stored.
   * @param string $directory
   *   The directory to scan in each extension to scan for files.
   * @param string $collection
   *   The collection to store configuration in.
   * @param bool $include_profile
   *   Whether to include the install profile in extensions to
   *   search and to get overrides from.
   * @param string $profile
   *   The current installation profile.
   */
  public function __construct(StorageInterface $config_storage, $directory, $collection, $include_profile, $profile) {
    parent::__construct($directory, $collection);
    $this->configStorage = $config_storage;
    $this->includeProfile = $include_profile;
    $this->installProfile = $profile;
  }

  /**
   * {@inheritdoc}
   */
  public function createCollection($collection) {
    return new static($this->configStorage, $this->directory, $collection, $this->includeProfile, $this->installProfile);
  }

  /**
   * Returns a map of all config object names and their folders.
   *
   * The list is based on enabled modules and themes. The active configuration
   * storage is used rather than \Drupal\Core\Extension\ModuleHandler and
   *  \Drupal\Core\Extension\ThemeHandler in order to resolve circular
   * dependencies between these services and \Drupal\Core\Config\ConfigInstaller
   * and \Drupal\Core\Config\TypedConfigManager.
   *
   * @return array
   *   An array mapping config object names with directories.
   */
  protected function getAllFolders() {
    if (!isset($this->folders)) {
      $this->folders = [];
      $this->folders += $this
        ->getCoreNames();
      $extensions = $this->configStorage
        ->read('core.extension');

      // @todo Remove this scan as part of https://www.drupal.org/node/2186491
      $listing = new ExtensionDiscovery(\Drupal::root());
      if (!empty($extensions['module'])) {
        $modules = $extensions['module'];

        // Remove the install profile as this is handled later.
        unset($modules[$this->installProfile]);
        $profile_list = $listing
          ->scan('profile');
        if ($this->installProfile && isset($profile_list[$this->installProfile])) {

          // Prime the \Drupal\Core\Extension\ExtensionList::getPathname()
          // static cache with the profile info file location so we can use
          // ExtensionList::getPath() on the active profile during the module
          // scan.
          // @todo Remove as part of https://www.drupal.org/node/2186491

          /** @var \Drupal\Core\Extension\ProfileExtensionList $profile_extension_list */
          $profile_extension_list = \Drupal::service('extension.list.profile');
          $profile_extension_list
            ->setPathname($this->installProfile, $profile_list[$this->installProfile]
            ->getPathname());
        }
        $module_list_scan = $listing
          ->scan('module');
        $module_list = [];
        foreach (array_keys($modules) as $module) {
          if (isset($module_list_scan[$module])) {
            $module_list[$module] = $module_list_scan[$module];
          }
        }
        $this->folders += $this
          ->getComponentNames($module_list);
      }
      if (!empty($extensions['theme'])) {
        $theme_list_scan = $listing
          ->scan('theme');
        foreach (array_keys($extensions['theme']) as $theme) {
          if (isset($theme_list_scan[$theme])) {
            $theme_list[$theme] = $theme_list_scan[$theme];
          }
        }
        $this->folders += $this
          ->getComponentNames($theme_list);
      }
      if ($this->includeProfile) {

        // The install profile can override module default configuration. We do
        // this by replacing the config file path from the module/theme with the
        // install profile version if there are any duplicates.
        if ($this->installProfile) {
          if (!isset($profile_list)) {
            $profile_list = $listing
              ->scan('profile');
          }
          if (isset($profile_list[$this->installProfile])) {
            $profile_folders = $this
              ->getComponentNames([
              $profile_list[$this->installProfile],
            ]);
            $this->folders = $profile_folders + $this->folders;
          }
        }
      }
    }
    return $this->folders;
  }

}