[Bug 34128] "Log out" dialog should not offer options that do not log out

[Phil Housley]

Public bug reported:
https://launchpad.net/malone/bugs/34128

Affects: gnome-session (Ubuntu)
       Severity: Normal
       Priority: (none set)
         Status: Unconfirmed

Description:
The current logout dialog really does not make sense.  Why should a user
click "log out" if they actually want to switch user or lock the screen?
Any option that does not involve logging out should not be accessed by
selecting "log out" from the menu.

As "lock screen" is already in the menu, it can be removed from the
dialog with no other changes.  It would make sense to also move "switch
user" to the top menu, provided switching users is considered to be
mature enough in gdm.

Finally, if the top level "log out" option is to make sense, it needs to
be made clear that all actions selectable from the dialog will actually
log you out, as well as whatever else they might do (eg. shutting down.)
The obvious elements would be "log out and: <buttons>" and "just log
out."