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

src/api.cc

Index: src/api.cc
diff --git a/src/api.cc b/src/api.cc
index db5da6f9f8978ea1818039c3072c434cee523e64..8a5cf4b0680fd1264ea12b972d50d1aa894cd94c 100644
--- a/src/api.cc
+++ b/src/api.cc
@@ -3755,8 +3755,7 @@ MaybeLocal<Array> v8::Object::GetPropertyNames(Local<Context> context) {
   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
@@ -3778,9 +3777,9 @@ 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