Mark ServiceWorkerContainer.onerror as supported only in Firefox (#10761)
Mark ServiceWorkerContainer.onerror as supported only in Firefox (#10761)

The existing data was incorrect.

https://mdn-bcd-collector.appspot.com/tests/api/ServiceWorkerContainer/onerror
was used to manually confirm no support in:
 - Chrome 90
 - Edge 18 (also checked `navigator.serviceWorker.onerror`)
 - Safari 14.1

Additionally, the string "onerror" has never appeared in Chromium or
WebKit source, confirmed with `git log -S onerror` on these files:
https://source.chromium.org/chromium/chromium/src/+/main:third_party/blink/renderer/modules/service_worker/service_worker_container.idl;l=1;drc=af69d93ec0d5334cdc03316058660a37116f32b3
https://github.com/WebKit/WebKit/blob/217b2531a97f217b61eb4f501666291e2a64a14f/Source/WebCore/workers/service/ServiceWorkerContainer.idl

https://bugzilla.mozilla.org/show_bug.cgi?id=1714533 was filed and
linked for Firefox. The ESR notes aren't important here.

Finally, this can't be considered experimental, more like accidental.
chrisdavidmills/browser-compat-data,chrisdavidmills/browser-compat-data,mdn/browser-compat-data,mdn/browser-compat-data