/usr/share/gtk-doc/html/libgimpbase/ is in libgimp2.0-doc 2.8.16-1ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/gtk-doc/html/libgimpbase/home.png
/usr/share/gtk-doc/html/libgimpbase/index.html
/usr/share/gtk-doc/html/libgimpbase/index.sgml
/usr/share/gtk-doc/html/libgimpbase/left-insensitive.png
/usr/share/gtk-doc/html/libgimpbase/left.png
/usr/share/gtk-doc/html/libgimpbase/libgimpbase-gimpbaseenums.html
/usr/share/gtk-doc/html/libgimpbase/libgimpbase-gimpbasetypes.html
/usr/share/gtk-doc/html/libgimpbase/libgimpbase-gimpchecks.html
/usr/share/gtk-doc/html/libgimpbase/libgimpbase-gimpcpuaccel.html
/usr/share/gtk-doc/html/libgimpbase/libgimpbase-gimpdatafiles.html
/usr/share/gtk-doc/html/libgimpbase/libgimpbase-gimpenv.html
/usr/share/gtk-doc/html/libgimpbase/libgimpbase-gimplimits.html
/usr/share/gtk-doc/html/libgimpbase/libgimpbase-gimpmemsize.html
/usr/share/gtk-doc/html/libgimpbase/libgimpbase-gimpparam.html
/usr/share/gtk-doc/html/libgimpbase/libgimpbase-gimpparasite.html
/usr/share/gtk-doc/html/libgimpbase/libgimpbase-gimpparasiteio.html
/usr/share/gtk-doc/html/libgimpbase/libgimpbase-gimprectangle.html
/usr/share/gtk-doc/html/libgimpbase/libgimpbase-gimpsignal.html
/usr/share/gtk-doc/html/libgimpbase/libgimpbase-gimpunit.html
/usr/share/gtk-doc/html/libgimpbase/libgimpbase-gimputils.html
/usr/share/gtk-doc/html/libgimpbase/libgimpbase-gimpversion.html
/usr/share/gtk-doc/html/libgimpbase/libgimpbase-index-deprecated.html
/usr/share/gtk-doc/html/libgimpbase/libgimpbase-index-new-in-2-2.html
/usr/share/gtk-doc/html/libgimpbase/libgimpbase-index-new-in-2-4.html
/usr/share/gtk-doc/html/libgimpbase/libgimpbase-index-new-in-2-6.html
/usr/share/gtk-doc/html/libgimpbase/libgimpbase-index-new-in-2-8.html
/usr/share/gtk-doc/html/libgimpbase/libgimpbase-index.html
/usr/share/gtk-doc/html/libgimpbase/libgimpbase.devhelp2
/usr/share/gtk-doc/html/libgimpbase/libgimpbase.html
/usr/share/gtk-doc/html/libgimpbase/right-insensitive.png
/usr/share/gtk-doc/html/libgimpbase/right.png
/usr/share/gtk-doc/html/libgimpbase/style.css
/usr/share/gtk-doc/html/libgimpbase/up-insensitive.png
/usr/share/gtk-doc/html/libgimpbase/up.png