Reimplement Maps and Sets in JS

src/templates.js

 // Copyright 2014 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.
 
 "use strict";
 
 var callSiteCache = new $Map;
 
 function SameCallSiteElements(rawStrings, other) {
   var length = rawStrings.length;
   var other = other.raw;
 
   if (length !== other.length) return false;
 
   for (var i = 0; i < length; ++i) {
     if (rawStrings[i] !== other[i]) return false;
   }
 
   return true;
 }
 
 
 function GetCachedCallSite(siteObj, hash) {
-  var obj = %MapGet(callSiteCache, hash);
+  var obj = %_CallFunction(callSiteCache, hash, $MapGet);
 
   if (IS_UNDEFINED(obj)) return;
 
   var length = obj.length;
   for (var i = 0; i < length; ++i) {
     if (SameCallSiteElements(siteObj, obj[i])) return obj[i];
   }
 }
 
 
 function SetCachedCallSite(siteObj, hash) {
-  var obj = %MapGet(callSiteCache, hash);
+  var obj = %_CallFunction(callSiteCache, hash, $MapGet);
   var array;
 
   if (IS_UNDEFINED(obj)) {
     array = new InternalArray(1);
     array[0] = siteObj;
-    %MapSet(callSiteCache, hash, array);
+    %_CallFunction(callSiteCache, hash, array, $MapSet);
   } else {
     obj.push(siteObj);
   }
 
   return siteObj;
 }
 
 
 function GetTemplateCallSite(siteObj, rawStrings, hash) {
   var cached = GetCachedCallSite(rawStrings, hash);
 
   if (!IS_UNDEFINED(cached)) return cached;
 
   %AddNamedProperty(siteObj, "raw", %ObjectFreeze(rawStrings),
       READ_ONLY | DONT_ENUM | DONT_DELETE);
 
   return SetCachedCallSite(%ObjectFreeze(siteObj), hash);
 }