backport 757255: Fix bug reported by Pino: in kparts apps, selecting a toolbar like "mainToolBar <Part>" would show
the stuff related to "mainToolBar <Shell>". Using the toolbar name as userData was a bad idea indeed,
let's just use the index and iterate the same way the combo was filled in.

svn path=/branches/KDE/4.0/kdelibs/; revision=757258