ServiceWorker static routing API (w3c#1701)

This API allows developers to configure the routing, and allows them to offload simple things ServiceWorkers do. If the condition matches, the navigation happens without starting ServiceWorkers or executing JavaScript, which allows web pages to avoid performance penalties due to ServiceWorker interceptions.

Explainer: https://github.com/WICG/service-worker-static-routing-api
TAG review: w3ctag/design-reviews#863

Co-authored-by: Takashi Nakayama <tnak@chromium.org>
Co-authored-by: Shunya Shishido <sisidovski@users.noreply.github.com>
Co-authored-by: Marijn Kruisselbrink <mek@chromium.org>