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

src/builtins.cc

 // 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.
 
 #include "src/builtins.h"
 
 #include "src/api.h"
 #include "src/api-natives.h"
 #include "src/arguments.h"
 #include "src/base/once.h"
@@ skipping 1584 matching lines @@
   Handle<Object> object = args.atOrUndefined(isolate, 1);
   Maybe<bool> result = object->IsJSReceiver()
                            ? JSReceiver::TestIntegrityLevel(
                                  Handle<JSReceiver>::cast(object), SEALED)
                            : Just(true);
   MAYBE_RETURN(result, isolate->heap()->exception());
   return isolate->heap()->ToBoolean(result.FromJust());
 }
 
 
+// ES6 section 19.1.2.14 Object.keys ( O )
+BUILTIN(ObjectKeys) {
+  HandleScope scope(isolate);
+  Handle<Object> object = args.atOrUndefined(isolate, 1);
+  Handle<JSReceiver> receiver;
+  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, receiver,
+                                     Execution::ToObject(isolate, object));
+  Handle<FixedArray> keys;
+  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
+      isolate, keys,
+      JSReceiver::GetKeys(receiver, JSReceiver::OWN_ONLY, ENUMERABLE_STRINGS,
+                          CONVERT_TO_STRING));
+  return *isolate->factory()->NewJSArrayWithElements(keys);
+}
+
+
 // ES6 section 19.1.2.15 Object.preventExtensions ( O )
 BUILTIN(ObjectPreventExtensions) {
   HandleScope scope(isolate);
   Handle<Object> object = args.atOrUndefined(isolate, 1);
   if (object->IsJSReceiver()) {
     MAYBE_RETURN(JSReceiver::PreventExtensions(Handle<JSReceiver>::cast(object),
                                                Object::THROW_ON_ERROR),
                  isolate->heap()->exception());
   }
   return *object;
@@ skipping 1696 matching lines @@
 BUILTIN_LIST_C(DEFINE_BUILTIN_ACCESSOR_C)
 BUILTIN_LIST_A(DEFINE_BUILTIN_ACCESSOR_A)
 BUILTIN_LIST_H(DEFINE_BUILTIN_ACCESSOR_H)
 BUILTIN_LIST_DEBUG_A(DEFINE_BUILTIN_ACCESSOR_A)
 #undef DEFINE_BUILTIN_ACCESSOR_C
 #undef DEFINE_BUILTIN_ACCESSOR_A
 
 
 }  // namespace internal
 }  // namespace v8