Getting XID of a Meta.Window

[Amy C <mathematical coffee gmail com>]

Hi all,

I'm trying to get the XID of a Meta.Window. (This is on order to
convert it into a GDK window so that I can call `set_decorations` and
remove window decoration for maximised windows. I know you can set
this in the metacity theme XML file, but I'm trying to do it with
JS/gobject introspection. I don't know how to convert it into a GTK
window (which has a convenient
`gtk_window_set_hide_titlebar_when_maximized` function that would  be
exactly what I wanted)).

On examining the Mutter sources it appears that I can get to the
window's actor and access the 'x-window' property:

    mutterWindow.get_compositor_private()['x-window']

However, this is not the window's XID (confirmed by using xwininfo on
the window).

Is there some way to get the window's XID, or otherwise convert it
into a G[DT]K window?

cheers!