Use import/export for more functions (instead of js builtins object).

src/js/prologue.js

 // Copyright 2015 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, extrasUtils) {
 
 "use strict";
 
 %CheckIsBootstrapping();
 
@@ skipping 145 matching lines @@
 function PostNatives(utils) {
   %CheckIsBootstrapping();
 
   for ( ; !IS_UNDEFINED(imports); imports = imports.next) {
     imports(exports_container);
   }
 
   // Whitelist of exports from normal natives to experimental natives and debug.
   var expose_list = [
     "ArrayToString",
+    "ErrorToString",
     "FunctionSourceString",
     "GetIterator",
     "GetMethod",
     "InnerArrayEvery",
     "InnerArrayFilter",
     "InnerArrayForEach",
     "InnerArrayIndexOf",
     "InnerArrayJoin",
     "InnerArrayLastIndexOf",
     "InnerArrayMap",
     "InnerArrayReduce",
     "InnerArrayReduceRight",
     "InnerArrayReverse",
     "InnerArraySome",
     "InnerArraySort",
     "InnerArrayToLocaleString",
     "IsNaN",
+    "MapEntries",
+    "MapIteratorNext",
     "MathMax",
     "MathMin",
     "ObjectIsFrozen",
     "ObjectDefineProperty",
     "ObserveArrayMethods",
     "ObserveObjectMethods",
     "OwnPropertyKeys",
+    "SetIteratorNext",
+    "SetValues",
     "SymbolToString",
     "ToNameArray",
+    "ToPositiveInteger",
     // From runtime:
     "is_concat_spreadable_symbol",
     "iterator_symbol",
     "promise_status_symbol",
     "promise_value_symbol",
     "reflect_apply",
     "reflect_construct",
     "to_string_tag_symbol",
   ];
 
@@ skipping 103 matching lines @@
 
 extrasUtils.uncurryThis = function uncurryThis(func) {
   return function(thisArg) {
     return %Apply(func, thisArg, arguments, 1, arguments.length - 1);
   };
 };
 
 %ToFastProperties(extrasUtils);
 
 })