[ServiceWorker] Allow waitUntil to be called multiple times asynchronously

third_party/WebKit/LayoutTests/external/wpt/service-workers/service-worker/resources/extendable-event-async-waituntil.js

Index: third_party/WebKit/LayoutTests/external/wpt/service-workers/service-worker/resources/extendable-event-async-waituntil.js
diff --git a/third_party/WebKit/LayoutTests/external/wpt/service-workers/service-worker/resources/extendable-event-async-waituntil.js b/third_party/WebKit/LayoutTests/external/wpt/service-workers/service-worker/resources/extendable-event-async-waituntil.js
index fc64e6ce567e3371ea9996d46d1cad76a66e5c88..9daf3087982eb71f3e765bbfdcede6595d8dd074 100644
--- a/third_party/WebKit/LayoutTests/external/wpt/service-workers/service-worker/resources/extendable-event-async-waituntil.js
+++ b/third_party/WebKit/LayoutTests/external/wpt/service-workers/service-worker/resources/extendable-event-async-waituntil.js
@@ -50,12 +50,24 @@ self.addEventListener('message', function(event) {
   });
 
 self.addEventListener('fetch', function(event) {
-    var resolveFetch;
-    let response = new Promise((res) => { resolveFetch = res; });
-    event.respondWith(response);
-    async_task_waituntil(event)
-      .then(reportResultExpecting('OK'))
-      .then(() => { resolveFetch(new Response('OK')); });
+    if (event.request.url.indexOf('pending-respondwith-async-waituntil') != -1) {
+      var resolveFetch;
+      let response = new Promise((res) => { resolveFetch = res; });
+      event.respondWith(response);
+      async_task_waituntil(event)
+        .then(reportResultExpecting('OK'))
+        .then(() => { resolveFetch(new Response('OK')); });
+    } else if (event.request.url.endsWith('respondwith-microtask-sync-waituntil') != -1) {
+      event.respondWith(Promise.resolve().then(() => {
+        sync_waituntil(event).then(reportResultExpecting('OK'));
+        return new Response('OK');
+        }));
+    } else if (event.request.url.endsWith('respondwith-microtask-async-waituntil') != -1) {
+      event.respondWith(Promise.resolve().then(() => {
+        async_microtask_waituntil(event).then(reportResultExpecting('OK'));
+        return new Response('OK');
+        }));
+    }
   });
 
 function reportResultExpecting(expectedResult) {