/usr/lib/x86_64-linux-gnu/libunity-webapps.so is in libunity-webapps-dev 2.5.0~+16.04.20160201-0ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libunity-webapps.so.0.0.0