Previous code was activating the networkAgent and telepathyClient
in the lock-screen, irrespective of the previous mode.
Now it checks if the session mode is locked down, and if so it refuses
to start new components.
https://bugzilla.gnome.org/show_bug.cgi?id=683400
Components are pieces of the shell code that can be added/removed
at runtime, like extension, but are tied more directly to a session
mode. The session polkit agent, the network agent, autorun/automount,
are all components, keyring, recorder and telepathy client are all
now copmonents.
https://bugzilla.gnome.org/show_bug.cgi?id=683156