[QA] Epic complete: Run browser tests against every MobileFrontend/Gather patch

[Jon Robson]

I've declared victory on
`[EPIC] Run browser tests against every MobileFrontend/Gather patch`
https://phabricator.wikimedia.org/T100293 after working out what the
next steps are [1]

We are doing this and the reading team have really taken this all the
way we can.  Gather, QuickSurveys and MobileFrontend will now prevent
you merging browser tests that break your code. For those who did not
see my recent e-mail thread -
http://www.gossamer-threads.com/lists/wiki/wikitech/625806 - has more
details.

The next stage for improving our QA infrastructure is to be
ambassadors and get other extensions doing what we are doing and push
Greg and the rest of the release engineering team to make browser
tests part of our deployment process.

Greg let me know if there is anything specific reading can do to move
this along.

We need to make sure we've documented our achievements to help move
this along. I have added https://phabricator.wikimedia.org/T104321 to
the next sprint.

Well done guys!
Jon

[1] https://phabricator.wikimedia.org/T101865