Use notification display service to collect persistent notifications.

chrome/test/data/notifications/platform_notification_service.html

Index: chrome/test/data/notifications/platform_notification_service.html
diff --git a/chrome/test/data/notifications/platform_notification_service.html b/chrome/test/data/notifications/platform_notification_service.html
index 88b2ac3e4c5f1cfe8c41ee8be80bf3ac7688ba7d..e1b1e93c90823370edd4b3f9794133e461a263be 100644
--- a/chrome/test/data/notifications/platform_notification_service.html
+++ b/chrome/test/data/notifications/platform_notification_service.html
@@ -21,6 +21,18 @@
         });
       }
 
+      function DisplayNonPersistentNotification(title, options) {
+        options = options || { body: 'Hello, world!', 
+                               icon: 'icon.png' };
+        var notification = null;
+        try {
+          notification = new Notification(title, options);
+          domAutomationController.send('ok');
+        } catch (error) {
+            domAutomationController.send('' + error);
+        }
+      }
+
       // Renews the registered Service Worker registration for this page, then
       // displays a notification on the activated ServiceWorkerRegistration.
       function DisplayPersistentNotification(title, options) {
@@ -127,6 +139,30 @@
         });
       }
 
+      // Gets a comma separated list of currently displayed notification titles
+      function GetDisplayedNotifications() {
+        GetActivatedServiceWorker('platform_notification_service.js',
+                                  location.pathname)
+          .then(function (sw) {
+            return sw.getNotifications();
+          }).then(function (notifications) {
+            var notificationResult = '';
+              for (var i = 0; i < notifications.length; ++i) {
+                notificationResult = notificationResult.concat(notifications[i].title);
+                  if (i < (notifications.length -1))
+                    notificationResult = notificationResult.concat(',');                    
+              }
+              if (expectingMessage)
+                domAutomationController.send(notificationResult);
+              else
+                messageStack.push(notificationResult);
+
+              domAutomationController.send('ok');
+          }).catch(function (error) {
+            domAutomationController.send('' + error);
+          });
+      }
+
       // Returns the latest received message from the worker. If no message has
       // been received, nothing will be done. For successfully registered
       // Service Workers this is OK, however, since the "message" event handler