function callback method argument crash with nativescript-plugin-firebase

Native stack trace:
1          0x10f9f4d6b tns::Assert(bool, v8::Isolate*) + 119
2          0x10f9607f9 tns::ArgConverter::Invoke(v8::Local<v8::Context>, objc_class*, v8::Local<v8::Object>, tns::V8Args&, tns::MethodMeta const*, bool) + 95
3          0x10f9ba9c0 tns::MetadataBuilder::InvokeMethod(v8::Local<v8::Context>, tns::MethodMeta const*, v8::Local<v8::Object>, tns::V8Args&, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >, bool) + 76
4          0x10f9ba513 tns::MetadataBuilder::PropertyGetterCallback(v8::FunctionCallbackInfo<v8::Value> const&) + 245
5          0x10fb2b3dc v8::internal::FunctionCallbackArguments::Call(v8::internal::CallHandlerInfo) + 620
6          0x10fb2a88c v8::internal::MaybeHandle<v8::internal::Object> v8::internal::(anonymous namespace)::HandleApiCallHelper<false>(v8::internal::Isolate*, v8::internal::Handle<v8::internal::HeapObject>, v8::internal::Handle<v8::internal::HeapObject>, v8::internal::Handle<v8::internal::FunctionTemplateInfo>, v8::internal::Handle<v8::internal::Object>, v8::internal::BuiltinArguments) + 556
7          0x10fb2a23a v8::internal::Builtins::InvokeApiFunction(v8::internal::Isolate*, bool, v8::internal::Handle<v8::internal::HeapObject>, v8::internal::Handle<v8::internal::Object>, int, v8::internal::Handle<v8::internal::Object>*, v8::internal::Handle<v8::internal::HeapObject>) + 762
8          0x10feb1c92 v8::internal::Object::GetPropertyWithAccessor(v8::internal::LookupIterator*) + 466
9          0x10feb13eb v8::internal::Object::GetProperty(v8::internal::LookupIterator*, bool) + 139
10         0x10fd28f05 v8::internal::LoadIC::Load(v8::internal::Handle<v8::internal::Object>, v8::internal::Handle<v8::internal::Name>, bool) + 1605
11         0x10fd3195e v8::internal::Runtime_LoadNoFeedbackIC_Miss(int, unsigned long*, v8::internal::Isolate*) + 286
12         0x1103b7619 Builtins_CEntry_Return1_DontSaveFPRegs_ArgvOnStack_NoBuiltinExit + 57
JavaScript stack trace:
at <anonymous> (file: node_modules/nativescript-plugin-firebase/firebase.ios.js:837:0)
at push.../node_modules/nativescript-plugin-firebase/firebase.js.GIDSignInDelegateImpl.signInDidSignInForUserWithError (file: node_modules/nativescript-plugin-firebase/firebase.ios.js:2175:0)

repro:

Just login via google with firebase plugin.

This works fine with JavaScriptCore ios-runtime.

node_modules/nativescript-plugin-firebase/firebase.ios.js の 837 行目と 2175 行目にある callback パスから始め、次に V8 iOS runtime で Google login を再現します。JavaScriptCore で同じフローを比較し、callback メソッドの引数周辺にある native assertion を追跡します。完了条件は、V8 で Google login がクラッシュしなくなることです。