Warning: Scope(Class[Site_config::Packages::Uninstall]): Could not look up qualified variable 'site_config::packages::build_essential::install_essential'; class site_config::packages::build_essential has not been evaluated

Got this on a deploy to leech:

warning: Scope(Class[Site_config::Packages::Uninstall]): Could not look up qualified variable 'site_config::packages::build_essential::install_essential'; class site_config::packages::build_essential has not been evaluated at /srv/leap/puppet/modules/site_config/manifests/packages/uninstall.pp:6

(from redmine: created on 2014-04-01, closed on 2014-04-05, relates #7834 (closed))