[api] Support CreationContext() on module namespace objects

Bug: v8:9713
Change-Id: I80b8f72ce4617b314f6c4991297a6464f67cbbec
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1807364Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63844}

src/init/bootstrapper.cc

@@ -3564,6 +3564,7 @@ void Genesis::InitializeGlobal(Handle<JSGlobalObject> global_object,
     Handle<Map> map = factory->NewMap(
         JS_MODULE_NAMESPACE_TYPE, JSModuleNamespace::kSize,
         TERMINAL_FAST_ELEMENTS_KIND, JSModuleNamespace::kInObjectFieldCount);
+    map->SetConstructor(native_context()->object_function());
     Map::SetPrototype(isolate(), map, isolate_->factory()->null_value());
     Map::EnsureDescriptorSlack(isolate_, map, 1);
     native_context()->set_js_module_namespace_map(*map);

test/cctest/test-modules.cc

@@ -573,6 +573,7 @@ TEST(ModuleNamespace) {
     Local<Value> ns = module->GetModuleNamespace();
     CHECK_EQ(Module::kInstantiated, module->GetStatus());
     Local<v8::Object> nsobj = ns->ToObject(env.local()).ToLocalChecked();
+    CHECK_EQ(nsobj->CreationContext(), env.local());
 
     // a, b
     CHECK(nsobj->Get(env.local(), v8_str("a")).ToLocalChecked()->IsUndefined());