filechoosercell: Store type_format in filechoosercell

filechoosercell: Store type_format in filechoosercell

The format of the type column depends on the the type_format, which
is stored in the filechooserwidget.  We get that setting by looking
for the filechooserwidget ancestor, which no longer works after recent
changes to the list views (it was fragile to begin with).  At one point,
the setting appears to have been dynamic, but now it is only loading
from GSettings, so let's simply do the same within FileChooserCell.