getBrowserInfo() errors in Chrome/Chromium

[tdulcet]

Continuation of #11 and #12. See #12 (comment):

As expected, I do get some errors in the console, but they are probably better fixed with #11:

I believe we will need to implement something similar to this: rugk/unicodify#23 (comment).

[rugk]

Okay, so IMHO the polyfill should handle this.

WOuld you mind to create an issue at https://github.com/mozilla/webextension-polyfill/?
Ah okay no, it does not do this: mozilla/webextension-polyfill#116

[rugk]

Okay, fixed it.

I did some crazy thing and decided to use the (long-upon a time written and nearly forgotten) tests for that…
#19

I know the tests are ugly and running them is a pain and I would not do so nowadays likely, but uff… let's ignore that.