protected function addPermissions(Node $node, &$doc)
    {
        if (!is_null($this->aclProvider)) {
            $roles = $this->getAclPermissions($node);
        } else {
            // Fallback when no ACL available / assume everything is accessible...
            $roles = array('IS_AUTHENTICATED_ANONYMOUSLY');
        }
        $doc['view_roles'] = $roles;
    }