Polyfill request animation in the test suite

[kumar303]

We load a polyfill in the web application for React 16 (search for import 'raf/polyfill') but not in the test suite. This litters the console with warnings. We should add that polyfill to the test suite, maybe in tests/setup.js.

[tofumatt]

Good call, thanks for noticing. The tests since moving to Jest have been so noisy that I run them with the --silent argument most of the time, so I missed this entirely. 😓

[willdurand]

Why would the reducers yield such warnings though? 🤔

[kumar303]

The tests since moving to Jest have been so noisy...

Yeah, when I get time I'm going to create a console reporter plugin to accomplish this: jestjs/jest#4156

[kumar303]

This depends on a new polyfill module introduced by mozilla/addons-frontend#4119

I'll fix this when that patch lands.

[kumar303]

A few of the tests in mozilla/addons-frontend#4182 kept failing with out of memory errors. I guess the Travis VM doesn't perform well with the polyfill. Instead of spending a lot of time investigating I'm just going to close this for now. Maybe there's another way to make the React warnings go away.