/**
  * Not part of the interface but will be used by the custom 'path_inc' file
  */
 public function whitelistRebuild($source = null)
 {
     // For each alias in the database, get the top level component of the
     // system path it corresponds to. This is the portion of the path before
     // the first '/', if present, otherwise the whole path itself.
     // PS: Sorry for hardcoded db_query()
     $this->whitelist = [];
     $storageWhitelist = $this->storage->getWhitelist();
     if (!$storageWhitelist) {
         $this->whitelist = [];
     } else {
         foreach ($storageWhitelist as $path) {
             $this->whitelist[$path] = true;
         }
     }
     variable_set('path_alias_whitelist', $this->whitelist);
 }