- Prefer GURL() when we want to return a non-reference empty URL.
- In ServiceWorkerMain::GetStorageKey(), use a reference instead
of instantiating a new temporary GURL.
From url/gurl.h:
> // Returns a reference to a singleton empty GURL. This object is for
> // callers who return references but don't have anything to return in
> // some cases. If you just want an empty URL for normal use, prefer
> // GURL().
* feat: ServiceWorkerMain
* refactor: disconnect remote
* handle version_info_ nullptr case
* initiate finish request when possible and enumerate errors
* explicit name for test method
* oops
* fix: wait for redundant version to stop before destroying
* docs: clarify when undefined is returned
* chore: remove extra semicolons
