Figure out why the add-on requests login so often

[ianb]

We have 327MM login events, and a lot of activity as a result. Something is going crazy in the add-on.

[ianb]

The only place that makes these requests is addon/lib/user.js in initialize() – so we need to backtrack from there

[ianb]

Best theory so far is the loop removed in 02d175a

[ianb]

We've seen some improvement, we still have a small handful of clients (3?) who are sending a large number of requests. We'll need to revisit to see if, as the 2.6 xpi goes out, that improves. If the theory in the last comment is right, then this is a regression in 1.0.

[ianb]

Looking at GA events, I realize the open-browser event and the api-login event match, and are both at very high numbers. open-browser is sent whenever main.js:exports.main is called, while api-login is sent by the server when the actual call is made.

So some set of clients are getting that exports.main function called over and over. It's just supposed to be called on load (per the docs), but clearly something weirder is happening for some small number of people.

If the add-on is really being loaded and unloaded, then it's hard to do much, though we could look for the login cookie. If the function is being called a lot, then we can use a timer to suppress over-calling.