Add Flutter support

[collinjackson]

Flutter is a new project to help developers build high-performance, high-fidelity, mobile apps for iOS and Android from a single codebase. Flutter developers need the firebase-dart package to add Firebase support to their app.

Here is an example of a Firebase app using Flutter: https://github.com/flutter/firechat-flutter

Mojo is the IPC system that Flutter apps use to call native iOS and Android SDKs. By refactoring firebase-dart into a JavaScript and Mojo backend with a common interface, we can allow the firebase-dart package to work for Flutter developers. We will need dart-lang/sdk#24581 to be fixed before we can do this.

[kevmoo]

Waiting on dart-lang/sdk#24581

[olostan]

Is this issue is still active as Flutter now use not IPC way of communication with native services?

We really need Firebase in Flutter, and currently dart-lang/sdk#24581 is mostly implemented (only DDC part is left that has no relation to Flutter)

[collinjackson]

I closed the pull request since the mojo approach no longer works in Flutter.

I'd love to see Firebase database wrappers using the Flutter HostMessages API, but I'm not working on them at the moment.

[mit-mit]

This is now available here: https://github.com/flutter/plugins/blob/master/FlutterFire.md

[Janamou]

@kevmoo can we close this?