/usr/share/doc/libvala-0.16-0-dbg/changelog.Debian.gz is in libvala-0.16-0-dbg 0.16.1-2ubuntu4.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/libvala-0.16-0-dbg/../libvala-0.16-0/changelog.Debian.gz