Using GTK+ without an X11 Server

[Anthony <tony outpost24 com>]

Is there a way to run a Gtk+-based application without having it use an
actual X11 server? I know that there's a dummy/null-head X11 Driver, but
is it possible to have GDK/Gtk+ not even talk to an X11 server at all?
The reason I ask is that I need to do some automated testing using
WebKitGtk and it would be really convenient (maybe even faster?) to not
have it require an X11 server.

Thanks,
 - Tony