CVE-2012-6111

In hardy, gnome_keyring_lock_all_sync() was in the gnome-keyring
package, and works as expected.
In 2.30+ in Lucid+, gnome_keyring_lock_all_sync() is in
libgnome-keyring and sends a LockService DBus call to
gnome-keyring. This call isn't implemented in lucid+
Nothing in the archive in Oneiric+ actually uses
gnome_keyring_lock_all_sync(), so this is low.
In Lucid, gnome-power-manager calls this before suspend and
hibernation with the intention of locking the keyring.
Fixing this in Lucid would result in the user likely having to
retype their keyring password when coming out of suspend and
hibernation, which is an intrusive change this late in Lucid's
lifecycle.
Setting this issue as priority low for the reasons above.