[gegl] shift: remove outdated XXX comment about abyss policy

[Øyvind Kolås <ok src gnome org>]

commit 9fcb6f3709d838f29abae44438c69d7f796d2546
Author: Øyvind Kolås <pippin gimp org>
Date:   Wed Sep 16 21:49:44 2015 +0200

    shift: remove outdated XXX comment about abyss policy

 operations/common/shift.c |    2 --
 1 files changed, 0 insertions(+), 2 deletions(-)
---
diff --git a/operations/common/shift.c b/operations/common/shift.c
index de6f015..1aea0a5 100644
--- a/operations/common/shift.c
+++ b/operations/common/shift.c
@@ -119,8 +119,6 @@ process (GeglOperation       *operation,
           src_rect.y = result->y + shift;
         }
 
-      /* XXX: gegl_buffer_copy doesn't allow to set the abyss policy,
-       * but we probably need _CLAMP here */
       gegl_buffer_copy (input, &src_rect, GEGL_ABYSS_CLAMP,
                         output, &dst_rect);
     }