DragDropAction: Fix crash

Author: leolost2605

lib/DragDropAction.vala

@@ -145,6 +145,8 @@ namespace Gala {
         }
 
         private void release_actor (Actor actor) {
+            actor.weak_unref (actor_dispose_notify);
+
             if (DragDropActionType.SOURCE in drag_type) {
 
                 var source_list = sources.@get (drag_id);
@@ -155,8 +157,6 @@ namespace Gala {
                 var dest_list = destinations[drag_id];
                 dest_list.remove (actor);
             }
-
-            actor.destroy.disconnect (release_actor);
         }
 
         private void connect_actor (Actor actor) {
@@ -181,7 +181,11 @@ namespace Gala {
                 dest_list.add (actor);
             }
 
-            actor.destroy.connect (release_actor);
+            actor.weak_ref (actor_dispose_notify);
+        }
+
+        private void actor_dispose_notify (Object obj) {
+            release_actor ((Clutter.Actor) obj);
         }
 
         private void emit_crossed (Actor destination, bool is_hovered) {