[gimp] Issue #4209: Animation optimize for GIF moves layers to top left corner.

[Jehan <jehanp src gnome org>]

commit 9a4d1f0277fb2ed6a79f83401b97b17e36698d04
Author: Jehan <jehan girinstud io>
Date:   Sun Nov 24 21:54:57 2019 +0100

    Issue #4209: Animation optimize for GIF moves layers to top left corner.
    
    Regression from commit 9d33a9a9ca8 as spotted by Massimo.

 plug-ins/common/animation-optimize.c | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/plug-ins/common/animation-optimize.c b/plug-ins/common/animation-optimize.c
index dfaa30a926..97e7134b1c 100644
--- a/plug-ins/common/animation-optimize.c
+++ b/plug-ins/common/animation-optimize.c
@@ -1145,6 +1145,7 @@ do_optimizations (GimpRunMode  run_mode,
                                GEGL_AUTO_ROWSTRIDE);
 
               g_object_unref (buffer);
+              gimp_item_transform_translate (GIMP_ITEM (new_layer), bbox_left, bbox_top);
             }
 
           gimp_progress_update (((gdouble) this_frame_num + 1.0) /