Added generics to typed interfaces

[dcworldwide]

The addition of types are ok, it helps catch API compliance with the compiler.

However without generics, there are a whole class of potential runtime errors that could have been easily caught at compile time.

Adding generics, will save an immeasurable amount of effort for integrators, by eliminating basic bugs that would have otherwise led to lost developer productivity and reduced software quality.

[google-oss-bot]

I couldn't figure out how to label this issue, so I've labeled it for a human to triage. Hang tight.

[looptheloop88]

@dcworldwide, thanks for the feedback. We highly suggest to follow the template when filling a bug or feature request, so we can properly label the issue. For example, indicate the Firebase product, relevant codes, etc..

[dcworldwide]

Ok my bad.

Using fb auth, rt database modules.

[looptheloop88]

Ok my bad.

Using fb auth, rt database modules.

Thanks, @dcworldwide.