[test-ui] Replaced hbox with hpaned
[test-ui] Replaced hbox with hpaned

Now we can move bar between both panels.

jasuarez/grilo,GNOME/grilo,grilofw/grilo,grilofw/grilo,MathieuDuponchelle/grilo,kyoushuu/grilo,GNOME/grilo,kyoushuu/grilo,kyoushuu/grilo,jasuarez/grilo,jasuarez/grilo,MathieuDuponchelle/grilo,grilofw/grilo,kyoushuu/grilo,MathieuDuponchelle/grilo