In keeping with Adobe's convention, Set and Map's forEach() function takes an optional 'thisObject' param

git-svn-id: svn+ssh://src.earth.threerings.net/narya/trunk@5502 542714f4-19e9-0310-aa3c-eee0fc999fb1

src/as/com/threerings/util/Set.as

@@ -42,7 +42,7 @@ public interface Set
     function contains (o :Object) :Boolean;
 
     /** Call the specified function, which accepts an element as an argument. */
-    function forEach (fn :Function) :void;
+    function forEach (fn :Function, thisObject :* = null) :void;
 
     /** Retuns the number of elements in this set. */
     function size () :int; // @TSC - should this be uint?