/usr/lib/linux-tools/3.19.0-79-lowlatency/cpupower is in linux-tools-3.19.0-79-lowlatency 3.19.0-79.87~14.04.1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/linux-tools/3.19.0-79-lowlatency/../../linux-lts-vivid-tools-3.19.0-79/cpupower