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

Source/bindings/tests/results/core/V8TestInterfaceCheckSecurity.cpp

Index: Source/bindings/tests/results/core/V8TestInterfaceCheckSecurity.cpp
diff --git a/Source/bindings/tests/results/core/V8TestInterfaceCheckSecurity.cpp b/Source/bindings/tests/results/core/V8TestInterfaceCheckSecurity.cpp
index b9911dc2f4117b26fb2824b7c0171dcde4c9c18b..eca012d76fb96a5551a9089b070f91e7b527d32b 100644
--- a/Source/bindings/tests/results/core/V8TestInterfaceCheckSecurity.cpp
+++ b/Source/bindings/tests/results/core/V8TestInterfaceCheckSecurity.cpp
@@ -543,6 +543,10 @@ static void installV8TestInterfaceCheckSecurityTemplate(v8::Local<v8::FunctionTe
     };
     V8DOMConfiguration::installAttribute(isolate, instanceTemplate, v8::Local<v8::ObjectTemplate>(), doNotCheckSecurityUnforgeableVoidMethodOriginSafeAttributeConfiguration);
 
+    instanceTemplate->Set(v8::Symbol::GetToStringTag(isolate), v8AtomicString(isolate, "TestInterfaceCheckSecurity"));
+
+    prototypeTemplate->Set(v8::Symbol::GetToStringTag(isolate), v8AtomicString(isolate, "TestInterfaceCheckSecurityPrototype"));
+
     // Custom toString template
     functionTemplate->Set(v8AtomicString(isolate, "toString"), V8PerIsolateData::from(isolate)->toStringTemplate());
 }