NullReferenceException in FirebaseAuthGoogleImplementation.HandleActivityResultAsync

[Dreamescaper]

The suggested DI setup for Google Auth is the following:

        builder.Services.AddSingleton(_ => CrossFirebaseAuthGoogle.Current);

Meaning that this service is lazy, not created until requested.
However, that leads to a failure in FirebaseAuthGoogleImplementation.HandleActivityResultAsync if IFirebaseAuthGoogle wasn't ever requested.

So in my case, OnActivityResult is invoked for reasons not related to Google Auth. FirebaseAuthGoogleImplementation.HandleActivityResultAsync should simply do nothing. But because FirebaseAuthGoogleImplementation._googleAuth is null, it fails with NRE.

I was able to workaround that be replacing DI setup with this:

builder.Services.AddSingleton(CrossFirebaseAuthGoogle.Current);

In this case, FirebaseAuthGoogleImplementation is initialized on startup, and therefore doesn't fail. However, that probable negatively affects startup performance.