src: use v8::Isolate::TryGetCurrent() in DumpJavaScriptBacktrace()
It was using Isolate::GetCurrent() which DCHECK on nullptr, even though what we wanted was to return early if it is nullptr.
Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
It was using Isolate::GetCurrent() which DCHECK on nullptr, even though what we wanted was to return early if it is nullptr.