To be fair, Rex isn't introducing the issue here, he just happens to be the first brave developers to add tests to `dialer.js` :)

I think it's fair to open of follow up for this since we have the issue in other places:

We could have 1 js file for each window (`index.js` and `oncall.js`) registering 1 listener to "load" and doing everything in it.
And those files wouldn't be loaded in the tests.

What do you guys think? Open to suggestions :)