Using username for popup name. This selects exactly the right
  name. Otherwise we'd pick one of the regions the click was made in, which
  wouldn't always select the right one.
When finding regions, prefer the user's ones.

Added sorting to keep the order in line (mostly for the tests).
Added optional 'user' parameter to the  method.
Note: this parameter isn't used yet, that's for the next commit.
Using find-by-username method from last commit
Using proper regions for popups