stage: if backend _ignoring_redraw_clips queue full redraw

stage: if backend _ignoring_redraw_clips queue full redraw

In clutter_stage_real_queue_redraw we were checking to see if the
backend will ignore any subsequent redraw_clip so we can avoid the cost
of projecting the paint-volume of an actor into stage coordinates, but
we weren't ensuring that a full redraw would be queued instead we just
bailed out immediately. This makes sure to call
_clutter_stage_window_add_redraw_clip (stage_window, NULL) in this case
to make sure the backend will do an un-clipped redraw.