Refactor integration/accessibility tests

[linuxwolf]

Connected to #9

This refactor better uses the Selenium-based webdriver and the underlying web-ext API to run integration functional/accessibility tests using the same patterns the unit tests use.

This also adds support for running accessibility testing via axe-webdriverjs (to start, the management homepage).

[jaredhirsch]

@linuxwolf On my mac, I'm not able to get npm run integration to correctly choose Nightly; it defaults to release channel Firefox, then the test fails, because the addon is unsigned. I think the binary needs to be explicitly set in the webdriver code (unless there's a command-line option I haven't discovered).

I found a reference snippet in a semi-recent blog post that seems relevant:

const binary = new firefox.Binary(firefox.Channel.NIGHTLY);
binary.addArguments("--headless");
const driver = new Builder()
  .forBrowser('firefox')
  .setFirefoxOptions(new firefox.Options().setBinary(binary))
  .build();

This doesn't immediately work here, because the firefox() getter inside driver.js causes breakage when trying to access firefox.Binary and firefox.Channel. A little juggling should get it working, though, I think?

[linuxwolf]

That's a good catch, and I'll add a way to set which Firefox to look for.

I lean toward making it configurable via environment variables and/or npm config properties, though. For instance, I really want automated testing to run against either unsigned or beta so we're not too bleeding edge.

[jaredhirsch]

LGTM, just a few minor things / questions

[jaredhirsch]

I'd probably ask somebody on the addons team (maybe @aswan?) if there's a better incantation to use here, just to be sure.

[linuxwolf]

That's a good point.

This was copied almost verbatim from lockbox-extension's test setup, and was a pattern I saw elsewhere, but it doesn't make it the best.

[linuxwolf]

@mozilla-lockbox/desktop-engineering mind doing another CR? There were some non-trivial changes to address the comments, and another pass seems worthwhile.

[linuxwolf]

merged with @6a68 's earlier r+