Introduce new content APIs for persistent notifications.

content/shell/browser/layout_test/layout_test_notification_manager.h

Index: content/shell/browser/layout_test/layout_test_notification_manager.h
diff --git a/content/shell/browser/layout_test/layout_test_notification_manager.h b/content/shell/browser/layout_test/layout_test_notification_manager.h
index 66bd61dca4cb3934caaec2df6eea987534edeaae..7792a7a108e7c9cb5a5fe9ce6e5280c7698fd119 100644
--- a/content/shell/browser/layout_test/layout_test_notification_manager.h
+++ b/content/shell/browser/layout_test/layout_test_notification_manager.h
@@ -53,6 +53,14 @@ class LayoutTestNotificationManager : public PlatformNotificationService {
                            scoped_ptr<DesktopNotificationDelegate> delegate,
                            int render_process_id,
                            base::Closure* cancel_callback) override;
+  void DisplayPersistentNotification(
+      BrowserContext* browser_context,
+      int64 service_worker_registration_id,
+      const ShowDesktopNotificationHostMsgParams& params,
+      int render_process_id) override;
+  void ClosePersistentNotification(
+      BrowserContext* browser_context,
+      const std::string& persistent_notification_id) override;
 
  private:
   // Closes the notification titled |title|. Must be called on the UI thread.