Workaround regression in database backend due to css_classes
Workaround regression in database backend due to css_classes

Note that we still need to check how css_classes shall be treated in the
database backed staticpages case.

DanielNeugebauer/adhocracy,phihag/adhocracy,phihag/adhocracy,liqd/adhocracy,alkadis/vcv,alkadis/vcv,DanielNeugebauer/adhocracy,alkadis/vcv,phihag/adhocracy,liqd/adhocracy,liqd/adhocracy,liqd/adhocracy,phihag/adhocracy,alkadis/vcv,DanielNeugebauer/adhocracy,phihag/adhocracy,DanielNeugebauer/adhocracy,DanielNeugebauer/adhocracy,alkadis/vcv