function handleFetch(event) {
  event.respondWith(new Response("intercepted"));
}

self.oninstall = function (event) {
  addEventListener("fetch", handleFetch);
  self.onfetch = handleFetch;
};

// Bug 1325101. Make sure adding event listeners for other events
// doesn't set the fetch flag.
addEventListener("push", function () {});
addEventListener("message", function () {});
addEventListener("non-sw-event", function () {});