Function updatePortal

docs/external/js/react-dom.development.js:13721–13733

(returnFiber, current, portal, expirationTime)

    }

    function updatePortal(returnFiber, current, portal, expirationTime) {
      if (current === null || current.tag !== HostPortal || current.stateNode.containerInfo !== portal.containerInfo || current.stateNode.implementation !== portal.implementation) {
        // Insert
        var created = createFiberFromPortal(portal, returnFiber.mode, expirationTime);
        created.return = returnFiber;
        return created;
      } else {
        // Update
        var existing = useFiber(current, portal.children || []);
        existing.return = returnFiber;
        return existing;
      }
    }

    function updateFragment(returnFiber, current, fragment, expirationTime, key) {
      if (current === null || current.tag !== Fragment) {