Fix for Bug 686892, bbox device returns empty box

This is a reminder.

Log:
When bbox device is being opened, bbox_copy_params is called and colors
should
be remapped. But because of r1.9 patch, the color remapping process is
ignored
as 'is_open' flag is false. To determine whether color remapping should be 
done, I made to check if dev_proc(bdev, get_color_mapping_procs) is valid.

Jeong

Index: src/gdevbbox.c
===================================================================
RCS file: /cvs/ghostscript/gs/src/gdevbbox.c,v
retrieving revision 1.15
diff -C2 -r1.15 gdevbbox.c
*** src/gdevbbox.c	14 Oct 2003 12:43:18 -0000	1.15
--- src/gdevbbox.c	11 Jan 2004 23:52:57 -0000
***************
*** 223,227 ****
      if (tdev != 0)
  	gx_device_copy_params((gx_device *)bdev, tdev);
!     if (remap_colors && bdev->is_open) {
  	bdev->black = gx_device_black((gx_device *)bdev);
  	bdev->white = gx_device_white((gx_device *)bdev);
--- 223,227 ----
      if (tdev != 0)
  	gx_device_copy_params((gx_device *)bdev, tdev);
!     if (remap_colors && dev_proc(bdev, get_color_mapping_procs)) {
  	bdev->black = gx_device_black((gx_device *)bdev);
  	bdev->white = gx_device_white((gx_device *)bdev);