NetworkManager stopped touching /etc/hosts in late 2010 before the
NetworkManager 0.8.1 release.  The code in nm-policy-hosts.c's only
purpose is to remove any of the entries that NetworkManager added long
ago.

I think we're at the point where people have already upgraded to
NetworkManager 0.8.1 or later and thus this code would be a NOP.  The
only risk is that some stale /etc/hosts entries will be left if you
upgrade from NM 0.8 or lower to anything higher than that.

FWIW, Ubuntu Lucid (10.04) ships NM 0.8.0 and SLES11 ships NM 0.7.0, so
if users of these distros upgraded to a later NetworkManager they might
run into the stale entries issue if we remove this code from NM.  But
given how old these distros are, it seems unlikely that users will do a
direct upgrade to something 4+ years newer...

https://bugzilla.gnome.org/show_bug.cgi?id=729689