[gimp] app: make "gegl:matting-levin" default engine of Foreground Select tool.

[Jehan <jehanp src gnome org>]

commit b52cdf4c90800452aa9717d57398ba72a5819d2a
Author: Jehan <jehan girinstud io>
Date:   Mon Jul 6 22:16:01 2020 +0200

    app: make "gegl:matting-levin" default engine of Foreground Select tool.
    
    Even though this engine is optional, we already have the code to detect
    its absence at runtime, and to fallback to "gegl:matting-global". So it
    won't be a problem even then.
    
    When the operation is present though, it definitely makes a lot more
    sense than matting global as default, because it performs a lot better
    in most cases (as far as I could see as well as others).

 app/tools/gimpforegroundselectoptions.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/app/tools/gimpforegroundselectoptions.c b/app/tools/gimpforegroundselectoptions.c
index c5ad98c723..220936f637 100644
--- a/app/tools/gimpforegroundselectoptions.c
+++ b/app/tools/gimpforegroundselectoptions.c
@@ -120,7 +120,7 @@ gimp_foreground_select_options_class_init (GimpForegroundSelectOptionsClass *kla
                          _("Engine"),
                          _("Matting engine to use"),
                          GIMP_TYPE_MATTING_ENGINE,
-                         GIMP_MATTING_ENGINE_GLOBAL,
+                         GIMP_MATTING_ENGINE_LEVIN,
                          GIMP_PARAM_STATIC_STRINGS);
 
   GIMP_CONFIG_PROP_INT  (object_class, PROP_LEVELS,