Install iterator meta objects via utils object.

src/js/collection.js

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 (function(global, utils) {
 "use strict";
 
 %CheckIsBootstrapping();
 
 // -------------------------------------------------------------------
 // Imports
 
 var GlobalMap = global.Map;
 var GlobalObject = global.Object;
 var GlobalSet = global.Set;
 var hashCodeSymbol = utils.ImportNow("hash_code_symbol");
 var IntRandom;
+var MapIterator;
+var NumberIsNaN;
+var SetIterator;
 var toStringTagSymbol = utils.ImportNow("to_string_tag_symbol");
 
 utils.Import(function(from) {
   IntRandom = from.IntRandom;
-});
-
-var NumberIsNaN;
-
-utils.Import(function(from) {
+  MapIterator = from.MapIterator;
   NumberIsNaN = from.NumberIsNaN;
+  SetIterator = from.SetIterator;
 });
 
 // -------------------------------------------------------------------
 
 function HashToEntry(table, hash, numBuckets) {
   var bucket = ORDERED_HASH_TABLE_HASH_TO_BUCKET(hash, numBuckets);
   return ORDERED_HASH_TABLE_BUCKET_AT(table, bucket);
 }
 %SetForceInlineFlag(HashToEntry);
 
@@ skipping 455 matching lines @@
   "map_from_array", MapFromArray,
   "set_from_array",SetFromArray,
 ]);
 
 utils.Export(function(to) {
   to.GetExistingHash = GetExistingHash;
   to.GetHash = GetHash;
 });
 
 })