[Bug] Onboarding - Blank screen after tapping Sign in, Sign in

[grigoryk]

In the logs, I'm seeing the following:

FirefoxAccountStateMachine  D  Processing event Init for state Start. Next state is Start
                         D  Got invalid event Authenticate for state Start.
                         D  Ran 'Init' side-effects for state Start, got successive event AccountNotFound
                         D  Processing event AccountNotFound for state Start. Next state is NotAuthenticated
            AppServices  I  Using fxaclient_ffi_lib_name: fenix
          fxaclient_ffi  D  fxa_new
              GeckoView  W  No GeckoSession attached to this GeckoView instance. Call setSession to attach a GeckoSession to this instance.

Seems like state events are not being processed in the right order.

Steps to reproduce

With a fresh Fenix install, click "Sign in" in the onboarding flow, then "sign in" again.

Expected behavior

FxA sign-in page.

Actual behavior

Blank screen. Going back, and tapping "sign in" again fixes the problem.

Device information

• Android device: ?
• Fenix version: ?

┆Issue is synchronized with this Jira Task

[grigoryk]

Makes perfect sense that trying this flow again fixes the problem. At that point we're already in the 'AccountNotFound' state, and process the 'Authenticate' event correctly.

[grigoryk]

The simplest thing to do here is at the application level - we need to make sure accountManager is initialized before we try interacting with it.

Good thing about this is that we need to do this anyway for the onboarding flow: it should check our signed-in status, and adjust the UI accordingly; which means registering for account change events with the accountManager.