[gimp] app: fix layer-mask offset when applying filter to layer without clipping

[Ell <ell src gnome org>]

commit f9fb3e6fad65cd69c328ed1ef64b5b3d6281f22f
Author: Ell <ell_se yahoo com>
Date:   Fri Aug 9 21:13:36 2019 +0300

    app: fix layer-mask offset when applying filter to layer without clipping

 app/core/gimpdrawable-filters.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/app/core/gimpdrawable-filters.c b/app/core/gimpdrawable-filters.c
index 56adbe1ee2..ee23eb3f74 100644
--- a/app/core/gimpdrawable-filters.c
+++ b/app/core/gimpdrawable-filters.c
@@ -258,7 +258,7 @@ gimp_drawable_merge_filter (GimpDrawable *drawable,
                                 gimp_get_default_context (image->gimp),
                                 GIMP_FILL_TRANSPARENT,
                                 rect.width, rect.height,
-                                rect.x, rect.y);
+                                -rect.x, -rect.y);
 
               gimp_image_undo_group_end (image);
             }