Some clients can be "undone", removing their effects and deleting any saved
state. For example, xmodmap could register a resign command to undo the
keymap changes it saved.
Used by clients that use the GTK2.GNOME_RESTART_ANYWAY restart style to undo
their effects (these clients usually perform initialization functions and
leave effects behind after they die). The resign command combines the
effects of a shutdown command and a discard command. It is executed when
the user decides that the client should cease to be restarted.
Not implemented yet.