Comment 45 for bug 1771858

Tested 229-4ubuntu21.22 on Xenial:

ubuntu@ubuntu-Standard-PC-i440FX-PIIX-1996:~$ sudo systemd-run /usr/bin/env
[sudo] password for ubuntu:
Running as unit run-r22d04a00a8304e2da719773bb14b6fb4.service.
ubuntu@ubuntu-Standard-PC-i440FX-PIIX-1996:~$ journalctl -a | grep PATH
Jul 02 14:31:04 ubuntu-Standard-PC-i440FX-PIIX-1996 env[2093]: PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/snap/bin
ubuntu@ubuntu-Standard-PC-i440FX-PIIX-1996:~$ dpkg -l systemd
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name Version Architecture Description
+++-=======================-================-================-===================================================
ii systemd 229-4ubuntu21.22 amd64 system and service manager
ubuntu@ubuntu-Standard-PC-i440FX-PIIX-1996:~$ dmesg | grep initr
[ 0.243635] Unpacking initramfs...
[ 0.891349] Freeing initrd memory: 54320K

The fix for Xenial does not depend on snapd's environment generator, just hardcodes including /snap/bin in the PATH.