Use serverSocket in middleware and expose window.karma.socket

I'd like to be able to reuse Karma's web socket in my middleware. I cannot do this because I run into circular dependency. Is there no way to do that?

Start by tracing how middleware accesses the serverSocket and how window.karma is exposed. Resolve the circular dependency question and define the intended serverSocket and window.karma.socket behavior before determining what tests should verify.

Written by the indexing model from the issue text.