Fix pager mini-index drawing when $pager_index_lines = 1 and $status_on_top.

Fix pager mini-index drawing when $pager_index_lines = 1 and $status_on_top.

When $pager_index_lines is 1, there is room for the index status line,
but not for any actual index entries.  The index redraw part was
always calling menu_redraw_current() which doesn't actually check if
there is room for the current row.

This bug only shows up with $status_on_top, due to the order things
are redrawn.