Comment 9 for bug 220563

FFE request:

The following patches will make the process extremely easy for users so that:
1) the user tries to enable an external monitor (a la xinerama)
2) if screen-resolution-extra is installed:
she is asked the permission to change the virtual resolution and then she's told to log out and log back in.
Otherwise if screen-resolution-extra is not installed:
she is asked to change the virtual resolution manually to what the gtk dialog suggests and to log out and log back in.
Either way her settings are saved in ~/.config/monitos.xml.desired
3) On next login, if everything's ok (i.e. the connected outputs are the same and the framebuffer is enough), the gnome-settings-daemon will load the settings from ~/.config/monitos.xml.desired and the user will have her multiple screens layout automatically applied without problems.

This will require:
1 patch for gnome-desktop (which is used by gnome-settings-daemon)
1 patch for gnome-control-center (which uses gnome-desktop and screen-resolution-extra, the latter being only an option, not a dependency)
an update of screen-resolution-extra so that it only applies the settings without duplicating the calculation of the required framebuffer (now done in gnome-desktop)

See the debdiffs attached below.