Spec (started by @Mooeypoo):
- Enable cross-wiki notifications
- Have Puppet create the tracking table.
- More than 2 wikis (so, 3 at least) so we can verify that bundles work from multiple wikis and not just from 1 remote wiki.
- To allow testing all of F2969695 (depending on what the current unread are), different languages of the same project (French Wikipedia, Hebrew Wikipedia), different projects in the same language (French Wikipedia and French Wiktionary), and an outlier (Chinese Wikivoyage).
- We'll need Flow, Thanks and Echo (of course) to be active in all of them. Flow and Thanks would be useful as base extensions to give cross-wiki notifications, but I guess they're not absolutely a must if we have other notification-producing extensions in there.
- Ideally, we should control the languages of those wikis (though I think that's a given in Vagrant?) For me, it would be awesome if one of those wikis was non-Latin and/or RTL for testing, or, at least, if we could relatively easily change its language/directionality for occasional testing.
- For browser testing, it would also be great if we could have all of the wikis initialize with "Selenium user a" and "Selenium user b" so we can test both local and remote notifications with browser tests automatically. (Though this point is probably not that urgent to have, and we can always add those manually when/if we decide to run cross-wiki proper browser tests)