Comment 4 for bug 1000238

Looks like line 176 of /usr/share/software-center/softwarecenter/ui/gtk3/views/appdetailsview.py is trying to call Gtk.ProgressBar.set_data(), which doesn't appear to be a valid method from what I see in the docs at http://www.pygtk.org/docs/pygtk/class-gtkprogressbar.html.