Fix crash in public mode introduced by #370

[maxpoulin64]

Oopsie. Just ran into it by accident.

[astorije]

I guess the purpose of this PR is to ensure that the config (or client.config depending on where it is used) is not null or undefined so that config.something / client.config.something does not crash the app.

However, why did you move from !client.config.token to, effectively, client.config.token?

[maxpoulin64]

Huh, yeah I think I made a mistake there. I need to switch it back to !. It is a problem with config being undefined indeed.

[maxpoulin64]

@astorije updated.

[astorije]

Follow-up question: in which case(s) can we end up with client.config being undefined or null? You said you ran into this, so I'm curious what led you there.

[maxpoulin64]

config is a user's .json file. In public mode, when a user connects, a temporary anonymous client is made and this one doesn't have a config. No config means no JSON, so no token no saving.