Expose ServiceWorkerRegistration.showNotification() in Service Workers.

LayoutTests/http/tests/notifications/resources/instrumentation-service-worker.js

Index: LayoutTests/http/tests/notifications/resources/instrumentation-service-worker.js
diff --git a/LayoutTests/http/tests/notifications/resources/instrumentation-service-worker.js b/LayoutTests/http/tests/notifications/resources/instrumentation-service-worker.js
new file mode 100644
index 0000000000000000000000000000000000000000..a0253c2096403b714cf5cce783718802847317c4
--- /dev/null
+++ b/LayoutTests/http/tests/notifications/resources/instrumentation-service-worker.js
@@ -0,0 +1,45 @@
+// Allows the controlling document to instrument Web Notification behavior
+// within a Service Worker by sending commands.
+var messagePort = null;
+
+addEventListener('message', function(workerEvent) {
+    messagePort = workerEvent.data;
+
+    // Listen to incoming commands on the message port.
+    messagePort.onmessage = function(event) {
+        if (typeof event.data != 'object' || !event.data.command)
+            return;
+
+        switch (event.data.command) {
+            case 'permission':
+                messagePort.postMessage({ command: 'permission', value: Notification.permission });
+                break;
+
+            case 'show':
+                registration.showNotification(event.data.title, event.data.options).then(function() {
+                    messagePort.postMessage({ command: 'show', success: true });
+                }, function(error) {
+                    messagePort.postMessage({ command: 'show', success: false, message: error.message });
+                });
+                break;
+
+            default:
+                messagePort.postMessage({ command: 'error', message: 'Invalid command: ' + event.data.command });
+                break;
+        }
+    };
+
+    // Notify the controller that the worker is now available.
+    messagePort.postMessage('ready');
+});
+
+addEventListener('notificationclick', function(event) {
+    messagePort.postMessage({ command: 'click', notification: {
+        title: event.notification.title
+    }});
+
+    // Notifications containing "ACTION:CLOSE" in their message will be closed
+    // immediately by the Service Worker.
+    if (event.notification.body.indexOf('ACTION:CLOSE') != -1)
+        event.notification.close();
+});