feat(aio): provide noop service worker file

Use this file if we need to turn off the service worker in deployed sites
in an emergency where the worker has a bug that is blocking the application
from working.

Closes #16897

aio/src/noop-worker-basic.js

@@ -0,0 +1,28 @@
+/**
+ * A simple, no-op service worker that takes immediate control.
+ * Use this file if the active service worker has a bug and we
+ * want to deactivate the worker on client browsers while we
+ * investigate the problem.
+ *
+ * To activate this service worker file, rename it to `worker-basic.min.js`
+ * and deploy to the hosting. When the original worker files cache
+ * expires, this one will take its place. (Browsers ensure that the expiry
+ * time is never longer than 24 hours, but the default expiry time on Firebase
+ * is 60 mins).
+ */
+
+// Skip over the "waiting" lifecycle state, to ensure that our
+// new service worker is activated immediately, even if there's
+// another tab open controlled by our older service worker code.
+self.addEventListener('install', function(event) {
+  event.waitUntil(self.skipWaiting());
+});
+
+
+// Get a list of all the current open windows/tabs under
+// our service worker's control, and force them to reload.
+// This can "unbreak" any open windows/tabs as soon as the new
+// service worker activates, rather than users having to manually reload.
+self.addEventListener('activate', function(event) {
+  event.waitUntil(self.clients.claim());
+});