upgrade from 1.10 to trunk cannot deploy containers

[William Reade]

...because the lxc package was not installed by cloudinit before we had containers available. sudo apt-get install lxc fixes this.

[John A Meinel (jameinel)]

It also spams the log file because it cannot find "lxc-ls".
Which causes that task to return an error, causing the runner to kill off the machiner environ-provider, apiserver upgrader and firewaller.
And then restart them, only to kill them, ad nauseum.

I don't think this is the same bug as https://bugs.launchpad.net/juju-core/+bug/1199915
But it is what I'm seeing right now trying to upgrade juju-core bootstrapped with 1.10 => trunk (using trunk)

[John A Meinel (jameinel)]

To clarify, missing 'lxc-ls' is killing that task, which ends up killing and restarting all tasks. So it isn't just that this spams the log file and cannot deploy containers, it actually breaks the running system after an upgrade until lxc is installed.