Custom validator

Fixed your issue with customValidatorUI.

The issue was a bit sneaky and I did actually ran into the very same issue back then. The app was configured to spawn a new stage ( = card in Mojo-speak) automatically. So the account app did request the custom UI, launched the app with the scene parameter and the app did push it's scene once to the accounts app and once to its own stage. The second thing happens without animation, so you don't notice. If you switch to card view, you suddenly see a stack with account app showing the custom valdiator UI and the app showing it, too.

As you might have noticed, there were two log outputs. One had a param, one did not. And this is the root cause of the issue. Only the scene in the account manager app had the param. If you would have switched back to account manager, the thing would have worked before already. :)

I now copied over the stuff needed to prevent webos from spawning a stage. Actually the "noWindow=true" setting in appinfo.json, might be enough. AFAIK then just nothing happens if you select the app from the launcher. Might not be the best thing... This way a new stage is created, if the app does not have one. This way the custom UI works in account manager without spawning a new card and the app itself can also do something (like display a help or something later on).