apt::params: Complete $xfacts.
apt::params: Complete $xfacts.

`$xfacts` now contains and guards all `lsb*` facts. Looking up any
`lsb*`-related fact should now always be done through `$::apt::xfacts`
to ensure that the values are always set to either the value of the fact
or undef. This avoids all sorts of kerfuffles with strict variables.

imphil/puppetlabs-apt,puppetlabs/puppetlabs-apt,imphil/puppetlabs-apt