request.auth.token.email not present in the rules

Question

Our app uses Firebase as the back end database. Firebase provides authentication for our app with google as the only provider. The authentication works fine. I am getting a "SUCCESS" in the authentication result. I would like to change my firebase rules so only the users that are present in a collection can access the data. For it, I have the rules in firebase to control access to the data. The rules are not working when I use any variables from request.auth.(where as the same works from a simulator)

Below rule working in both app and simulator:

match /restaurants/{$rId}/addresses/{document=**} {
    allow read, write : if get(/databases/$(database)/documents/users/abc@gmail.com).data.restaurantId == $rId;
}

Below rule NOT working from app but working in simulator

match /restaurants/{$rId}/addresses/{document=**} {
    allow read, write : if get(/databases/$(database)/documents/users/$(request.auth.token.email)).data.restaurantId == $rId;
}

I am sending the authentication request from the app as follows:

private void signIn() {
    Intent signInIntent = Auth.GoogleSignInApi.getSignInIntent(googleApiClient);
    startActivityForResult(signInIntent, RC_SIGN_IN);
}

Handling the authentication result below:

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);

    if (requestCode == RC_SIGN_IN) {
        GoogleSignInResult result = Auth.GoogleSignInApi.getSignInResultFromIntent(data);
        if (result.isSuccess()) {
             Toast.makeText(MyApplication.getAppContext(), "Login Successfull", Toast.LENGTH_LONG);
         }
    }
}

My firebase database contains the following structures

Users:

/users
   abc@gmail.com
            -restaurantId: "1" 

Restaurants:

/restaurants
   1
          addresses
                 local
                     -name: a
                 international
                     -name: b 

   2
          addresses
                 local
                     -name: c
                 international
                     -name: d 
   3
          addresses
                 local
                     -name: e
                 international
                     -name: f

I am able to see the Toast "Login successful" when the user tries to login with a valid password.

Should I save the authentication result in the onActivityResult so that further requests will have the request.auth.token.email present? Kinldy please guide me. Can anyone please let me know if I am doing anything wrong?