[gimp] app: copy the new GEGL property keys in gimp_param_spec_duplicate()

[Michael Natterer <mitch src gnome org>]

commit 43244bd4611e4b1ac914ec4d9b0458e996aa3991
Author: Michael Natterer <mitch gimp org>
Date:   Fri May 16 02:30:41 2014 +0200

    app: copy the new GEGL property keys in gimp_param_spec_duplicate()

 app/core/gimpparamspecs-duplicate.c |    9 +++++++++
 1 files changed, 9 insertions(+), 0 deletions(-)
---
diff --git a/app/core/gimpparamspecs-duplicate.c b/app/core/gimpparamspecs-duplicate.c
index e52c96e..387760e 100644
--- a/app/core/gimpparamspecs-duplicate.c
+++ b/app/core/gimpparamspecs-duplicate.c
@@ -244,5 +244,14 @@ gimp_param_spec_duplicate (GParamSpec *pspec)
                  g_type_name (G_TYPE_FROM_INSTANCE (pspec)), pspec->name);
     }
 
+  if (copy)
+    {
+      GQuark      quark = g_quark_from_static_string ("gegl-property-keys");
+      GHashTable *keys  = g_param_spec_get_qdata (pspec, quark);
+
+      if (keys)
+        g_param_spec_set_qdata (copy, quark, g_hash_table_ref (keys));
+    }
+
   return copy;
 }