/lib/udev/rules.d/60-unity8-common.rules is in unity8-common 8.12+16.04.20160401-0ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 | # Make local foreground session able to inject input
KERNEL=="uinput", SUBSYSTEM=="misc", TAG+="uaccess"
|