The offending line is line 50 in evince_forward_search. Change it to
window.SyncView(tex_file, (line_number,1), int(time.time()), dbus_interface="org.gnome.evince.Window")
and all should be well.
I'm thinking about switching my tex editor to vim. If I do this I'll provide a config file to connect the python dbus scripts behind evince_forward_search and evince_backward_search to vim.