/usr/share/gnome/help/gtk-doc-manual/ is in gtk-doc-tools 1.18-2.
This file is owned by root:root, with mode 0o755.
..
/usr/share/gnome/help/gtk-doc-manual/C/
/usr/share/gnome/help/gtk-doc-manual/C/fdl-appendix.xml
/usr/share/gnome/help/gtk-doc-manual/C/gtk-doc-manual.xml
/usr/share/gnome/help/gtk-doc-manual/bn_IN/
/usr/share/gnome/help/gtk-doc-manual/bn_IN/gtk-doc-manual.xml
/usr/share/gnome/help/gtk-doc-manual/de/
/usr/share/gnome/help/gtk-doc-manual/de/gtk-doc-manual.xml
/usr/share/gnome/help/gtk-doc-manual/el/
/usr/share/gnome/help/gtk-doc-manual/el/gtk-doc-manual.xml
/usr/share/gnome/help/gtk-doc-manual/en_GB/
/usr/share/gnome/help/gtk-doc-manual/en_GB/gtk-doc-manual.xml
/usr/share/gnome/help/gtk-doc-manual/es/
/usr/share/gnome/help/gtk-doc-manual/es/gtk-doc-manual.xml
/usr/share/gnome/help/gtk-doc-manual/fr/
/usr/share/gnome/help/gtk-doc-manual/fr/gtk-doc-manual.xml
/usr/share/gnome/help/gtk-doc-manual/gu/
/usr/share/gnome/help/gtk-doc-manual/gu/gtk-doc-manual.xml
/usr/share/gnome/help/gtk-doc-manual/sl/
/usr/share/gnome/help/gtk-doc-manual/sl/gtk-doc-manual.xml
/usr/share/gnome/help/gtk-doc-manual/sv/
/usr/share/gnome/help/gtk-doc-manual/sv/gtk-doc-manual.xml
/usr/share/gnome/help/gtk-doc-manual/ta/
/usr/share/gnome/help/gtk-doc-manual/ta/gtk-doc-manual.xml
/usr/share/gnome/help/gtk-doc-manual/te/
/usr/share/gnome/help/gtk-doc-manual/te/gtk-doc-manual.xml