This allows URLs to be passed through to the server (where they are
properly redirected), instead of serving `index.html` from the SW.
Known issue:
`/docs/` will be passed through to the server. `/docs` (without the
trailing slash) will be correctly treated as a navigation URL and
handled by the SW.
We don't link to `/docs/` from within the app, but if there are external
links to `/docs/` they will require a round-trip to the server and will
not work in offline mode.
PR Close#19795
AIO is currently using a beta version of @angular/service-worker.
Since that was implemented, the SW has been rewritten and released
as part of Angular 5.0.0. This commit updates AIO to use the latest
implementation, with an appropriate configuration file that caches
the various AIO assets in useful ways.
PR Close#19795
George Kalpakas
Alex Rickabaugh