ServiceWorker: Modernize postMessage tests for cleanup

third_party/WebKit/LayoutTests/http/tests/serviceworker/postmessage-msgport-to-client.html

Index: third_party/WebKit/LayoutTests/http/tests/serviceworker/postmessage-msgport-to-client.html
diff --git a/third_party/WebKit/LayoutTests/http/tests/serviceworker/postmessage-msgport-to-client.html b/third_party/WebKit/LayoutTests/http/tests/serviceworker/postmessage-msgport-to-client.html
index e1726bbe313f5380c171df77e7c7fcf9ab0ccaef..e00d72c2d4d1488f745135293c7e128c30301063 100644
--- a/third_party/WebKit/LayoutTests/http/tests/serviceworker/postmessage-msgport-to-client.html
+++ b/third_party/WebKit/LayoutTests/http/tests/serviceworker/postmessage-msgport-to-client.html
@@ -4,45 +4,41 @@
 <script src="../resources/testharnessreport.js"></script>
 <script src="resources/test-helpers.js"></script>
 <script>
-var t = async_test('postMessage MessagePorts from ServiceWorker to Client');
-t.step(function() {
-    var scope = 'resources/blank.html'
-    service_worker_unregister_and_register(
-        t, 'resources/postmessage-msgport-to-client-worker.js', scope)
-      .then(function(registration) {
+
+promise_test(t => {
+    var script = 'resources/postmessage-msgport-to-client-worker.js';
+    var scope = 'resources/blank.html';
+    var port;
+
+    return service_worker_unregister_and_register(t, script, scope)
+      .then(registration => {
+          add_completion_callback(() => registration.unregister());
           return wait_for_state(t, registration.installing, 'activated');
         })
-      .then(function() { return with_iframe(scope); })
-      .then(function(frame) {
-          var w = frame.contentWindow;
-          w.navigator.serviceWorker.onmessage = t.step_func(onMessage);
-          w.navigator.serviceWorker.controller.postMessage('ping');
+      .then(() => with_iframe(scope))
+      .then(frame => {
+          return new Promise(resolve => {
+              var w = frame.contentWindow;
+              w.navigator.serviceWorker.onmessage = resolve;
+              w.navigator.serviceWorker.controller.postMessage('ping');
+            });
         })
-      .catch(unreached_rejection(t));
-
-    var result = [];
-    var expected = [
-        'Acking value: 1',
-        'Acking value: 2',
-    ];
+      .then(e => {
+          port = e.ports[0];
+          port.postMessage({value: 1});
+          port.postMessage({value: 2});
+          port.postMessage({done: true});
+          return new Promise(resolve => { port.onmessage = resolve; });
+        })
+      .then(e => {
+          assert_equals(e.data.ack, 'Acking value: 1');
+          return new Promise(resolve => { port.onmessage = resolve; });
+        })
+      .then(e => {
+          assert_equals(e.data.ack, 'Acking value: 2');
+          return new Promise(resolve => { port.onmessage = resolve; });
+        })
+      .then(e => { assert_true(e.data.done); });
+  }, 'postMessage MessagePorts from ServiceWorker to Client');
 
-    function onMessage(e) {
-      var message = e.data;
-      if ('port' in message) {
-        var port = message.port;
-        port.postMessage({value: 1});
-        port.postMessage({value: 2});
-        port.postMessage({done: true});
-      } else if ('ack' in message) {
-        result.push(message.ack);
-      } else if ('done' in message) {
-        assert_array_equals(
-            result, expected,
-            'Worker should post back expected values via MessagePort.');
-        service_worker_unregister_and_done(t, scope);
-      } else {
-        assert_unreached('Got unexpected message from ServiceWorker');
-      }
-    }
-  });
 </script>