getUser calls are much more strict, and one place where this was found was
in the (un)subscribe start/end event handlers, which resulted in making the
Subscription class a bit stricter, regarding ::start and ::cancel at least.
Several minor fixes in many files were made due to this.
This does NOT touch the Foreign_link function, which should also have a more
strict getUser call. That is a future project.
Mikael Nordfeldth
Evan Prodromou
Siebrand Mazeland
Brion Vibber