We have code for this in gimp_proc_browser_dialog_new(), but it cannot
be moved in the object init() because this is a construction-time only
property. So this needs to be passed from the python call too.
I may have missed things. That is the problem of non-compiled script
languages. There is also a known warning:
> DeprecationWarning: Gtk.Dialog.set_alternative_button_order_from_array is deprecated
I'll see later about this one.
Push-time note: calling various functions is actually broken right now
in the console since the late API changes (it was working fine yesterday
evening when I tested the same python-console code). Pushing anyway for
now.
