[builtins] Migrate Object.getOwnPropertyDescriptor 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 1643 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;
 }
 
 
+// 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);
+  Handle<Name> key;
+  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, key,
+                                     Object::ToName(isolate, property));
+  // 3. Let desc be ? obj.[[GetOwnProperty]](key).
+  PropertyDescriptor desc;
+  Maybe<bool> found =
+      JSReceiver::GetOwnPropertyDescriptor(isolate, receiver, key, &desc);
+  MAYBE_RETURN(found, isolate->heap()->exception());
+  // 4. Return FromPropertyDescriptor(desc).
+  if (!found.FromJust()) return isolate->heap()->undefined_value();
+  return *desc.ToObject(isolate);
+}
+
+
 namespace {
 
 Object* GetOwnPropertyKeys(Isolate* isolate,
                            BuiltinArguments<BuiltinExtraArguments::kNone> args,
                            PropertyFilter filter) {
   HandleScope scope(isolate);
   Handle<Object> object = args.atOrUndefined(isolate, 1);
   Handle<JSReceiver> receiver;
   ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, receiver,
                                      Object::ToObject(isolate, object));
@@ skipping 2514 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