function getMainCarrier() {
  utils.GLOBAL_OBJ.__SENTRY__ = utils.GLOBAL_OBJ.__SENTRY__ || {
    extensions: {},
    hub: undefined,
  };
  return utils.GLOBAL_OBJ;
}
Replaces the current main hub with the passed one on the global object

@returns The old replaced hub

@deprecated Use `setCurrentClient()` instead.