In bug 1353638 we removed some WPT tests and files. The lint caught a problem with the manifest not being fully updated, but it did not catch all the problems. Specifically, the manifest on m-c currently references: service-workers/service-worker/registration-useCache.https.html But this file is no longer in the tree. When we uplifted to mozilla-beta the older lint implementation did catch the problem. Seems the new linter has a bug somewhere.