[proxies] allow duplicate keys for [[OwnPropertyKeys]] trap.

src/api.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/api.h"
 
 #include <string.h>  // For memcpy, strlen.
 #ifdef V8_USE_ADDRESS_SANITIZER
 #include <sanitizer/asan_interface.h>
 #endif  // V8_USE_ADDRESS_SANITIZER
@@ skipping 3737 matching lines @@
   // IsTemplateFor() ensures that iter.GetCurrent() can't be a Proxy here.
   return Utils::ToLocal(i::handle(iter.GetCurrent<i::JSObject>(), isolate));
 }
 
 
 MaybeLocal<Array> v8::Object::GetPropertyNames(Local<Context> context) {
   PREPARE_FOR_EXECUTION(context, "v8::Object::GetPropertyNames()", Array);
   auto self = Utils::OpenHandle(this);
   i::Handle<i::FixedArray> value;
   has_pending_exception =
-      !i::JSReceiver::GetKeys(self, i::JSReceiver::INCLUDE_PROTOS,
-                              i::ENUMERABLE_STRINGS)
+      !i::JSReceiver::GetKeys(self, i::INCLUDE_PROTOS, i::ENUMERABLE_STRINGS)
            .ToHandle(&value);
   RETURN_ON_FAILED_EXECUTION(Array);
   // Because we use caching to speed up enumeration it is important
   // to never change the result of the basic enumeration function so
   // we clone the result.
   auto elms = isolate->factory()->CopyFixedArray(value);
   auto result = isolate->factory()->NewJSArrayWithElements(elms);
   RETURN_ESCAPED(Utils::ToLocal(result));
 }
 
 
 Local<Array> v8::Object::GetPropertyNames() {
   auto context = ContextFromHeapObject(Utils::OpenHandle(this));
   RETURN_TO_LOCAL_UNCHECKED(GetPropertyNames(context), Array);
 }
 
 
 MaybeLocal<Array> v8::Object::GetOwnPropertyNames(Local<Context> context) {
   PREPARE_FOR_EXECUTION(context, "v8::Object::GetOwnPropertyNames()", Array);
   auto self = Utils::OpenHandle(this);
   i::Handle<i::FixedArray> value;
-  has_pending_exception = !i::JSReceiver::GetKeys(self, i::JSReceiver::OWN_ONLY,
-                                                  i::ENUMERABLE_STRINGS)
-                               .ToHandle(&value);
+  has_pending_exception =
+      !i::JSReceiver::GetKeys(self, i::OWN_ONLY, i::ENUMERABLE_STRINGS)
+           .ToHandle(&value);
   RETURN_ON_FAILED_EXECUTION(Array);
   // Because we use caching to speed up enumeration it is important
   // to never change the result of the basic enumeration function so
   // we clone the result.
   auto elms = isolate->factory()->CopyFixedArray(value);
   auto result = isolate->factory()->NewJSArrayWithElements(elms);
   RETURN_ESCAPED(Utils::ToLocal(result));
 }
 
 
@@ skipping 4763 matching lines @@
   Address callback_address =
       reinterpret_cast<Address>(reinterpret_cast<intptr_t>(callback));
   VMState<EXTERNAL> state(isolate);
   ExternalCallbackScope call_scope(isolate, callback_address);
   callback(info);
 }
 
 
 }  // namespace internal
 }  // namespace v8