/usr/share/gtk-doc/html/libwnck is in libwnck-dev 2.30.7-2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/gtk-doc/html/../../doc/libwnck-dev/html/libwnck
/usr/share/gtk-doc/html/../../doc/libwnck-dev/html/libwnck