The private format and type member variables were not being used by any
of the callers, so they can simply be removed. This also fixes a leak of
type which was introduced when switching from gdk_x11_get_xatom_name()
to XGetAtomName().
Fixes: e66f4396e ("x11: Avoid GDK API in X11 selections")
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2957>
When there are two (or more) concurrent XConvertSelection requests with
the same target, selection and window and the data is large enough for
SelectionNotify events to overlap. This can result in the affected streams
being considered completed without any data being transferred.
While regular mutter/shell code does not make use of concurrent
XConvertSelection requests with the same targets, some extensions might.
Such as for example a clipboard manager that like the built-in clipboard
manager tries to read the selection on owner-changed.
One potential solution would be to make sure the event is for the correct
property, but not all clients seem to support concurrent requests for the
same targets but different properties on the same window.
This commit instead changes the streams to use their own window which
seems to be more widely supported.
Fixes https://gitlab.gnome.org/GNOME/gnome-shell/-/issues/4034
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1812>
