[DO NOT LAND] Set @@toStringTag for DOM object prototypes

Source/bindings/tests/results/core/V8TestInterfaceConstructor4.cpp

Index: Source/bindings/tests/results/core/V8TestInterfaceConstructor4.cpp
diff --git a/Source/bindings/tests/results/core/V8TestInterfaceConstructor4.cpp b/Source/bindings/tests/results/core/V8TestInterfaceConstructor4.cpp
index f0d729a375d5da03b15dbc0403e8e6318372d2cc..e3f52be795cd604bbed58c1edef861a1d12e3f22 100644
--- a/Source/bindings/tests/results/core/V8TestInterfaceConstructor4.cpp
+++ b/Source/bindings/tests/results/core/V8TestInterfaceConstructor4.cpp
@@ -115,6 +115,10 @@ static void installV8TestInterfaceConstructor4Template(v8::Local<v8::FunctionTem
     v8::Local<v8::ObjectTemplate> prototypeTemplate = functionTemplate->PrototypeTemplate();
     ALLOW_UNUSED_LOCAL(prototypeTemplate);
 
+    instanceTemplate->Set(v8::Symbol::GetToStringTag(isolate), v8AtomicString(isolate, "TestInterfaceConstructor4"));
+
+    prototypeTemplate->Set(v8::Symbol::GetToStringTag(isolate), v8AtomicString(isolate, "TestInterfaceConstructor4Prototype"));
+
     // Custom toString template
     functionTemplate->Set(v8AtomicString(isolate, "toString"), V8PerIsolateData::from(isolate)->toStringTemplate());
 }