Find a way to remove this.userId and prevent restarting the publication when userId changes

[peerlibrary]

Find a way to remove this.userId and prevent restarting the publication when userId changes

[steph643]

For reference, here is the kind of issue associated with the automatic publication restart: meteor/meteor#4705

[mitar]

This is especially interesting now with the subscription data package. userId could be just something inside the subscription's reactive data context. So if one wants to depend on userId, it registers reactivity, otherwise not.

[mitar]

I opened: meteor/meteor#6441

[mitar]

After more thought. I think this is premature optimization. I think sharing subscriptions between logged in and not logged in users is not as common. And publish functions should anyway be very lightweight, mostly just doing ACL and copying data from one source to output. So rerunning should not be very costly, probably as costly as running ACLs again anyway.