Added CommandEvent.markAsHandled().

git-svn-id: svn+ssh://src.earth.threerings.net/narya/trunk@4430 542714f4-19e9-0310-aa3c-eee0fc999fb1

src/as/com/threerings/mx/events/CommandEvent.as

@@ -47,6 +47,16 @@ public class CommandEvent extends Event
         this.arg = arg;
     }
 
+    /**
+     * Mark this command as handled, stopping its propagation up the
+     * hierarchy.
+     */
+    public function markAsHandled () :void
+    {
+        preventDefault();
+        stopImmediatePropagation();
+    }
+
     override public function clone () :Event
     {
         return create(command, arg);

src/as/com/threerings/util/Controller.as

@@ -96,8 +96,7 @@ public class Controller
         if (handleAction(event.command, event.arg)) {
             // if we handle the event, stop it from moving outward to another
             // controller
-            event.preventDefault();
-            event.stopImmediatePropagation();
+            event.markAsHandled();
         }
     }