/usr/lib/x86_64-linux-gnu/libubuntu-download-manager-client.so.1 is in libubuntu-download-manager-client1 1.2+16.04.20160408-0ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libubuntu-download-manager-client.so.1.2.0