[builtins] Migrate Object.keys to C++.

src/js/v8natives.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) {
 
 %CheckIsBootstrapping();
 
 // ----------------------------------------------------------------------------
 // Imports
@@ skipping 193 matching lines @@
 
 function ObjectLookupSetter(name) {
   var receiver = this;
   if (IS_NULL(receiver) || IS_UNDEFINED(receiver)) {
     receiver = %GlobalProxy(ObjectLookupSetter);
   }
   return %LookupAccessor(TO_OBJECT(receiver), TO_NAME(name), SETTER);
 }
 
 
-function ObjectKeys(obj) {
-  obj = TO_OBJECT(obj);
-  var filter = PROPERTY_FILTER_ONLY_ENUMERABLE | PROPERTY_FILTER_SKIP_SYMBOLS;
-  return %GetOwnPropertyKeys(obj, filter);
-}
-
-
 // ES6 6.2.4.1
 function IsAccessorDescriptor(desc) {
   if (IS_UNDEFINED(desc)) return false;
   return desc.hasGetter() || desc.hasSetter();
 }
 
 
 // ES6 6.2.4.2
 function IsDataDescriptor(desc) {
   if (IS_UNDEFINED(desc)) return false;
@@ skipping 654 matching lines @@
   "__lookupGetter__", ObjectLookupGetter,
   "__defineSetter__", ObjectDefineSetter,
   "__lookupSetter__", ObjectLookupSetter
 ]);
 utils.InstallGetterSetter(GlobalObject.prototype, "__proto__", ObjectGetProto,
                     ObjectSetProto);
 
 // Set up non-enumerable functions in the Object object.
 utils.InstallFunctions(GlobalObject, DONT_ENUM, [
   // assign is added in bootstrapper.cc.
-  "keys", ObjectKeys,
+  // keys is added in bootstrapper.cc.
   "defineProperty", ObjectDefineProperty,
   "defineProperties", ObjectDefineProperties,
   "getPrototypeOf", ObjectGetPrototypeOf,
   "setPrototypeOf", ObjectSetPrototypeOf,
   "getOwnPropertyDescriptor", ObjectGetOwnPropertyDescriptor,
   "getOwnPropertyNames", ObjectGetOwnPropertyNames,
   // getOwnPropertySymbols is added in symbol.js.
   "is", SameValue,  // ECMA-262, Edition 6, section 19.1.2.10
   // deliverChangeRecords, getNotifier, observe and unobserve are added
   // in object-observe.js.
@@ skipping 297 matching lines @@
 
 utils.Export(function(to) {
   to.GetIterator = GetIterator;
   to.GetMethod = GetMethod;
   to.IsFinite = GlobalIsFinite;
   to.IsNaN = GlobalIsNaN;
   to.NumberIsNaN = NumberIsNaN;
   to.ObjectDefineProperties = ObjectDefineProperties;
   to.ObjectDefineProperty = ObjectDefineProperty;
   to.ObjectHasOwnProperty = ObjectHasOwnProperty;
-  to.ObjectKeys = ObjectKeys;
 });
 
 %InstallToContext([
   "object_value_of", ObjectValueOf,
 ]);
 
 })