'Test that when host-storage gives an error, return unknown.'

def test_update_volume_stats_error(self):

    self._fail_host_storage = True
    actual = self.driver.get_volume_stats(True)
    self.assertEqual('HGST', actual['vendor_name'])
    self.assertEqual('hgst', actual['storage_protocol'])
    self.assertEqual('unknown', actual['total_capacity_gb'])
    self.assertEqual('unknown', actual['free_capacity_gb'])
    self.assertEqual(0, actual['reserved_percentage'])
