public function popLastLocator()
    {
        $lastLocator = @$_COOKIE[self::LOCATOR_COOKIE_NAME];
        // Check whether a locator is set.
        if ($lastLocator) {
            // There is a locator. Clear its cookie.
            setcookie(
                self::LOCATOR_COOKIE_NAME,
                null,
                time() - 1 // Expire the cookie.
            );
        }

        return $lastLocator;
    }