/usr/share/doc/libxmmsclient++-glib-dev/changelog.Debian.gz is in libxmmsclient++-glib-dev 0.8+dfsg-2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/libxmmsclient++-glib-dev/../libxmmsclient++4/changelog.Debian.gz