There's no need to depend on gtk-doc to install .html files. See the tracking bug for details.
It is a bug, see: https://fedoraproject.org/wiki/PackagingDrafts/Revised_File_and_Directory_Ownership From the original bug #604169#c31 --- Which by my reading means that all packages which place files in /usr/share/gtk-doc/ should go ahead and own that dir. (root/root, mode 755). ---
This seems to be fixed on 1.9.8.