Migrate Object.getPrototypeOf from v8natives to builtins.

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-arguments.h"
 #include "src/api-natives.h"
 #include "src/api.h"
 #include "src/base/once.h"
@@ skipping 1778 matching lines @@
   Handle<Object> object = args.atOrUndefined(isolate, 1);
   if (object->IsJSReceiver()) {
     MAYBE_RETURN(JSReceiver::SetIntegrityLevel(Handle<JSReceiver>::cast(object),
                                                FROZEN, Object::THROW_ON_ERROR),
                  isolate->heap()->exception());
   }
   return *object;
 }
 
 
+// ES section 19.1.2.9 Object.getPrototypeOf ( O )
+BUILTIN(ObjectGetPrototypeOf) {
+  HandleScope scope(isolate);
+  Handle<Object> object = args.atOrUndefined(isolate, 1);
+
+  Handle<JSReceiver> receiver;
+  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
+      isolate, receiver, Object::ToObject(isolate, object));
+
+  Handle<Object> prototype;
+  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
+      isolate, prototype, JSReceiver::GetPrototype(isolate, receiver));
+
+  return *prototype;
+}
+
+
 // ES6 section 19.1.2.6 Object.getOwnPropertyDescriptor ( O, P )
 BUILTIN(ObjectGetOwnPropertyDescriptor) {
   HandleScope scope(isolate);
   // 1. Let obj be ? ToObject(O).
   Handle<Object> object = args.atOrUndefined(isolate, 1);
   Handle<JSReceiver> receiver;
   ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, receiver,
                                      Object::ToObject(isolate, object));
   // 2. Let key be ? ToPropertyKey(P).
   Handle<Object> property = args.atOrUndefined(isolate, 2);
@@ skipping 3537 matching lines @@
 BUILTIN_LIST_T(DEFINE_BUILTIN_ACCESSOR_T)
 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
 #undef DEFINE_BUILTIN_ACCESSOR_T
 #undef DEFINE_BUILTIN_ACCESSOR_H
 
 }  // namespace internal
 }  // namespace v8