Adding Firebase Auth

[KevinSchildhorn]

Adding support for Firebase Authentication

Adds a Login/Logout button in the settings screen, that will authenticate with google sign-in using Firebase. Then the user state is sent to the common code, to be used later.

Shared Code

• Adding UserContext and UserData for commonly saved user information
• Currently passing this information to the UserIdProvider for now, will be handled later
• Adding abstract AuthenticationService for calling for sign in / sign out from common ui to platform specific code
• Passing AuthenticationService into SettingsViewModel and using that for compose calls

Platform Code

• Adding new Id "co.touchlab.droidconauthtest" for testing
• Adding FirebaseAuth to android and iOS using Gradle and CocoaPods
• Adding FirebaseService which is implementation of AuthenticationService for each platform, to handle authentication
• Adding authentication listener in MainActivity and AppDelegate to save changes to the common code
• Adding the ClientID as a secret in Android. Not sure if this is needed

TODO

We are unsure about saving the clientID in public or as a secret. In android it is already a secret, however in iOS it's added in a URLScheme so it's more challenging to keep secret. Will look into this more.

Proof

Note for Android emulator you'll need to be signed into your emulator

[KevinSchildhorn]

Updated style

	signed in	signed out
android
ios