Recreate Test Suite

In legacy SDK we had a comprehensive test suite that was run via jpm test

WebExtensions use web-ext, but it does not provide test runner yet. There is a related, open issue at https://github.com/mozilla/web-ext/issues/5.

This issue is blocked until WebExtension test runner is implemented upstream, or a custom npm tests command is implemented locally AND we reach 80%+ test coverage

(updated 2017-12-02)

• npm test runs test suite with browser stub
• think about Browser detection (we have Firefox/Chrome/Brave specific workarounds in codebase)
• TODO: go over tests in legacy-sdk branch and add missing unit tests here
• Research if we are able to run integration tests against real browsers with assertions that check browser UI
  • https://firefox-puppeteer.readthedocs.io:

    Firefox Puppeteer provides a library to manipulate each visual section of Firefox’s browser UI. For example, there are different libraries for the tab bar, the navigation bar, etc.