/usr/lib/x86_64-linux-gnu/unity8/qml/mocks/libusermetrics/libusermetricsoutput.so is in unity8-fake-env 8.12+16.04.20160401-0ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/unity8/qml/mocks/libusermetrics/libusermetricsoutput.so.1