
Or else `glXQueryDrawable` will fail per the `GLX_EXT_buffer_age` spec:
> If querying GLX_BACK_BUFFER_AGE_EXT and <draw> is not bound to
> the calling thread's current context a GLXBadDrawable error is
> generated.
This mistake went unnoticed until `mtk_x11_error_trap_push` was introduced
(55e3b2e519
) because for some reason it is incapable of trapping
`glXQueryDrawable`. Prior to that it seems
`cogl_onscreen_glx_get_buffer_age` would trap and so always returned zero.
This means we're reenabling clipped redraws on X11 here for the first
time in a long time.
Closes: https://gitlab.gnome.org/GNOME/mutter/-/issues/3007
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/3255>