Clarify the docs for gtk_widget_set_has_window()
Clarify the docs for gtk_widget_set_has_window()

The previous version of the docs did not make it clear that has-window
is the defaults. Pointed out by Magnus Hjorth, bug 615474.
(cherry picked from commit 61e34032ec0365928824900ed256c4e57ce8dc6f)

johne53/MB3Gtk-2,Unity-Technologies/gtk,Distrotech/gtk,Unity-Technologies/gtk,johne53/MB3Gtk-2,Distrotech/gtk,johne53/MB3Gtk-2,Distrotech/gtk,Distrotech/gtk,Unity-Technologies/gtk,johne53/MB3Gtk-2,Unity-Technologies/gtk,Distrotech/gtk,johne53/MB3Gtk-2,Unity-Technologies/gtk