Use shared container to manage imports/exports.

src/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) {
+
+"use strict";
+
+%CheckIsBootstrapping();
+
+// -----------------------------------------------------------------------
+// Utils
+
+var imports = UNDEFINED;
+var exports = UNDEFINED;
+
+
+utils.Export = function Export(f) {
+  f.next = exports;
+  exports = f;
+};
+
+
+utils.Import = function Import(f) {
+  f.next = imports;
+  imports = f;
+};
+
+// -----------------------------------------------------------------------
+// To be called by bootstrapper
+
+utils.PostNatives = function() {
+  %CheckIsBootstrapping();
+
+  var container = {};
+  for ( ; !IS_UNDEFINED(exports); exports = exports.next) exports(container);
+  for ( ; !IS_UNDEFINED(imports); imports = imports.next) imports(container);
+
+  var expose_to_experimental = [
+    "MathMax",
+    "MathMin",
+  ];
+  var experimental = {};
+  %OptimizeObjectForAddingMultipleProperties(
+      experimental, expose_to_experimental.length);
+  for (var key of expose_to_experimental) experimental[key] = container[key];
+  %ToFastProperties(experimental);
+  container = UNDEFINED;
+
+  utils.Export = UNDEFINED;
+  utils.PostNatives = UNDEFINED;
+  utils.Import = function ImportFromExperimental(f) {
+    f(experimental);
+  };
+};
+
+})