Flutter - Wire up the Google Sign In Plugin for iOS

This video covers:

- Create a firebase app
- Install the GoogleServices-Info.plist
- Import the Google sign-in plugin
- Wire up the sign in

Firebase Console:
https://console.firebase.google.com/u/0/

Pub Google Sign In - Get the dependency
https://pub.dartlang.org/packages/google_sign_in

Google Sign In Plugin Source
https://github.com/flutter/plugins/tree/master/packages/google_sign_in

Google Sign In Plugin Example
https://github.com/flutter/plugins/tree/master/packages/google_sign_in/example

Google Sign In Plugin Example IOS Runner(App), Here's the info.plist
https://github.com/flutter/plugins/tree/master/packages/google_sign_in/example/ios/Runner