/usr/share/gtk-doc/html/ is in libecal1.2-dev 3.2.3-0ubuntu6.
This file is owned by root:root, with mode 0o755.
..
/usr/share/gtk-doc/html/libecal/
/usr/share/gtk-doc/html/libecal/annotation-glossary.html
/usr/share/gtk-doc/html/libecal/api-index-1.12.html
/usr/share/gtk-doc/html/libecal/api-index-2.22.html
/usr/share/gtk-doc/html/libecal/api-index-2.24.html
/usr/share/gtk-doc/html/libecal/api-index-2.26.html
/usr/share/gtk-doc/html/libecal/api-index-2.28.html
/usr/share/gtk-doc/html/libecal/api-index-2.30.html
/usr/share/gtk-doc/html/libecal/api-index-2.32.html
/usr/share/gtk-doc/html/libecal/api-index-3.0.html
/usr/share/gtk-doc/html/libecal/api-index-3.2.html
/usr/share/gtk-doc/html/libecal/api-index-deprecated.html
/usr/share/gtk-doc/html/libecal/api-index-full.html
/usr/share/gtk-doc/html/libecal/ch01.html
/usr/share/gtk-doc/html/libecal/ch02.html
/usr/share/gtk-doc/html/libecal/home.png
/usr/share/gtk-doc/html/libecal/index.html
/usr/share/gtk-doc/html/libecal/index.sgml
/usr/share/gtk-doc/html/libecal/left.png
/usr/share/gtk-doc/html/libecal/libecal-ECal.html
/usr/share/gtk-doc/html/libecal/libecal-ECalClient.html
/usr/share/gtk-doc/html/libecal/libecal-ECalClientView.html
/usr/share/gtk-doc/html/libecal/libecal-ECalComponent.html
/usr/share/gtk-doc/html/libecal/libecal-ECalView.html
/usr/share/gtk-doc/html/libecal/libecal-e-cal-check-timezones.html
/usr/share/gtk-doc/html/libecal/libecal-e-cal-recur.html
/usr/share/gtk-doc/html/libecal/libecal-e-cal-system-timezone.html
/usr/share/gtk-doc/html/libecal/libecal-e-cal-time-util.html
/usr/share/gtk-doc/html/libecal/libecal-e-cal-types.html
/usr/share/gtk-doc/html/libecal/libecal-e-cal-util.html
/usr/share/gtk-doc/html/libecal/libecal.devhelp2
/usr/share/gtk-doc/html/libecal/right.png
/usr/share/gtk-doc/html/libecal/style.css
/usr/share/gtk-doc/html/libecal/up.png