In history, glib didn't support sockets on Windows so Twisted implemented PortableGIReactor which does socket handling with selectreactor and uses glib for glib stuff.

In 2016 or so, glib fixed this oversight so now you can use sockets as channels with glib on Windows.

Thus, PortableGIReactor is no longer needed and the regular GIReactor is fine.

Make PortableGIReactor an alias for GIReactor instead of its own separate weird thing.