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

src/builtins.h

 // Copyright 2011 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.
 
 #ifndef V8_BUILTINS_H_
 #define V8_BUILTINS_H_
 
 #include "src/base/flags.h"
 #include "src/handles.h"
 
@@ skipping 74 matching lines @@
   V(GeneratorFunctionConstructor, kTargetAndNewTarget)         \
                                                                \
   V(GlobalEval, kTarget)                                       \
                                                                \
   V(ObjectAssign, kNone)                                       \
   V(ObjectCreate, kNone)                                       \
   V(ObjectFreeze, kNone)                                       \
   V(ObjectIsExtensible, kNone)                                 \
   V(ObjectIsFrozen, kNone)                                     \
   V(ObjectIsSealed, kNone)                                     \
+  V(ObjectKeys, kNone)                                         \
   V(ObjectPreventExtensions, kNone)                            \
   V(ObjectSeal, kNone)                                         \
   V(ObjectProtoToString, kNone)                                \
                                                                \
   V(ProxyConstructor, kNone)                                   \
   V(ProxyConstructor_ConstructStub, kTarget)                   \
                                                                \
   V(ReflectDefineProperty, kNone)                              \
   V(ReflectDeleteProperty, kNone)                              \
   V(ReflectGet, kNone)                                         \
@@ skipping 326 matching lines @@
   friend class BuiltinFunctionTable;
   friend class Isolate;
 
   DISALLOW_COPY_AND_ASSIGN(Builtins);
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_BUILTINS_H_