$Try_1_Post = function () {
          try {
            return $return();
          } catch ($boundEx) {
            return $error($boundEx);
          }
        }
Called on main thread when web worker completes processing, but tile has since been discarded
        Frees resources that would have been transferred to the tile object.
        Static method because the tile object no longer exists (the tile data returned by the worker is passed instead).