new_contents: # http://www.openstreetmap.org/way/287494678
  z = 18
  x = 77193
  y = 98529
  while z >= 16:
      assert_has_feature(
          z, x, y, 'buildings',
          { 'kind': 'building',
            'id': 287494678 })
  
      z -= 1
      x /= 2
      y /= 2
  
subject: Add test for missing building part seen in production.