[gegl] gegl: implement path serialization for gegl-chain

[Øyvind Kolås <ok src gnome org>]

commit 75754e4a6696ef1bb6e00b2d41d0ec046f16bc76
Author: Øyvind Kolås <pippin gimp org>
Date:   Thu Apr 13 03:54:48 2017 +0200

    gegl: implement path serialization for gegl-chain

 gegl/gegl-serialize.c |   12 ++++++++++++
 1 files changed, 12 insertions(+), 0 deletions(-)
---
diff --git a/gegl/gegl-serialize.c b/gegl/gegl-serialize.c
index 44d8646..0cc6c98 100644
--- a/gegl/gegl-serialize.c
+++ b/gegl/gegl-serialize.c
@@ -788,6 +788,18 @@ gegl_serialize2 (GeglNode *start, GeglNode *end, const char *basepath,
                       }
                     g_free (value);
                   }
+                else if (property_type == GEGL_TYPE_PATH)
+                  {
+                    gchar *svg_path;
+                    GeglPath *path;
+                    gegl_node_get (iter, properties[i]->name, &path, NULL);
+                    svg_path = gegl_path_to_string (path);
+                    g_object_unref (path);
+                    g_string_append_printf (s2, " %s='%s'", property_name,
+                                            svg_path);
+                    printed = TRUE;
+                    g_free (svg_path);
+                  }
                 else
                   {
                     g_warning (