A regression from 3.3.  Calc wouldn't display page background color
or image in print preview.  This was a side effect of the removal
of the high-contract mode.

In 3.3, Calc purpusefully wouldn't show background color/image when
the app is in high contrast mode.  Now that the mode has been removed,
the code acted as though the high contract mode is always on, which
caused the background color/image to always be hidden in print preview.