Run Android Lint in Gutenberg Repo

[mchowning]

Summary

I would like us to start running Android lint checks in the Gutenberg PR checks.

Problem

Currently, we do not run Android lint checks in the Gutenberg repository. WPAndroid, however, does run lint on all the Android code in the build, which includes the Android code in Gutenberg. As a result, code that violates lint in Gutenberg passes the Gutenberg and gb-mobile PR builds just fine. When we try to update the submodule hash in WPAndroid, however, that PR build will fail, and we can only fixing it by going back and updating gutenberg.

Solution

I think there are two steps we need to take to solve this problem:

1. Add the Android lint checks to the Gutenberg PR process (I don't think there's any native code in gb-mobile, so we don't need it here?); and
2. Once that is done, update the WPAndroid lint checks to exclude gutenberg. This seems important because it will avoid us having to keep the lint checks perfectly in sync between the two projects. Otherwise, I imagine they would eventually get out of sync and we'd be in a scenario where the code that is needed to pass one of the lint checks causes the other lint check to fail.