ESLint 2 now flags anonymous generator functions according to
generator-star-spacing. Most of the changes here are correcting that.
MozReview-Commit-ID: 9xg2Gmlaz94
Also added a new utility module aboutdebugging/modules/worker.js
to extract the worker related logic that does not belong in components.
MozReview-Commit-ID: LvArq5cdMtT