That "nss-myhostname" message & correcting the /etc/hosts file

[Adam Funk]

I'm getting the

   systemd-hostnamed[15205]: Warning: nss-myhostname is not
   installed. Changing the local hostname might make it
   unresolveable. Please install nss-myhostname!

message in my logcheck output.  Looking it up says not to install the
equivalent package but to fix the /etc/hosts file.

<https://askubuntu.com/questions/453072/what-is-nss-myhostname-and-why-is-it-not-installable>

This is on a recent clean install of 14.04, upgraded immediately to
14.10 (because someone in the office had a 14.04 CD handy), using
DHCP.  I have not manually altered any of the networking stuff since
the installation.  The only thing possibly funny that I see in
/etc/hosts is that the "127.0.0.1  localhost" line is followed by one
with "127.0.0.1" and the hostname that the DHCP server gave (in fully
qualified and short forms).

Should I delete the second line?

Why does the Ubuntu installation set up /etc/hosts wrong?

Thanks,
Adam