/usr/share/devhelp/books/gstreamer-plugins-1.0 is in gstreamer1.0-doc 1.2.3-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/devhelp/books/../../doc/gstreamer1.0-doc/gstreamer-plugins-1.0
/usr/share/devhelp/books/../../doc/gstreamer1.0-doc/gstreamer-plugins-1.0