diff -r 000000000000 -r 6474c204b198 services/sync/modules/notifications.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/services/sync/modules/notifications.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,128 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+this.EXPORTED_SYMBOLS = ["Notifications", "Notification", "NotificationButton"];
+
+const Cc = Components.classes;
+const Ci = Components.interfaces;
+const Cr = Components.results;
+const Cu = Components.utils;
+
+Cu.import("resource://services-common/observers.js");
+Cu.import("resource://gre/modules/Log.jsm");
+Cu.import("resource://services-sync/util.js");
+
+this.Notifications = {
+  // Match the referenced values in toolkit/content/widgets/notification.xml.
+  get PRIORITY_INFO()     1, // PRIORITY_INFO_LOW
+  get PRIORITY_WARNING()  4, // PRIORITY_WARNING_LOW
+  get PRIORITY_ERROR()    7, // PRIORITY_CRITICAL_LOW
+
+  // FIXME: instead of making this public, dress the Notifications object
+  // to behave like an iterator (using generators?) and have callers access
+  // this array through the Notifications object.
+  notifications: [],
+
+  _observers: [],
+
+  // XXX Should we have a helper method for adding a simple notification?
+  // I.e. something like |function notify(title, description, priority)|.
+
+  add: function Notifications_add(notification) {
+    this.notifications.push(notification);
+    Observers.notify("weave:notification:added", notification, null);
+  },
+
+  remove: function Notifications_remove(notification) {
+    let index = this.notifications.indexOf(notification);
+
+    if (index != -1) {
+      this.notifications.splice(index, 1);
+      Observers.notify("weave:notification:removed", notification, null);
+    }
+  },
+
+  /**
+   * Replace an existing notification.
+   */
+  replace: function Notifications_replace(oldNotification, newNotification) {
+    let index = this.notifications.indexOf(oldNotification);
+
+    if (index != -1)
+      this.notifications.splice(index, 1, newNotification);
+    else {
+      this.notifications.push(newNotification);
+      // XXX Should we throw because we didn't find the existing notification?
+      // XXX Should we notify observers about weave:notification:added?
+    }
+
+    // XXX Should we notify observers about weave:notification:replaced?
+  },
+
+  /**
+   * Remove all notifications that match a title. If no title is provided, all
+   * notifications are removed.
+   *
+   * @param title [optional]
+   *        Title of notifications to remove; falsy value means remove all
+   */
+  removeAll: function Notifications_removeAll(title) {
+    this.notifications.filter(function(old) old.title == title || !title).
+      forEach(function(old) this.remove(old), this);
+  },
+
+  // replaces all existing notifications with the same title as the new one
+  replaceTitle: function Notifications_replaceTitle(notification) {
+    this.removeAll(notification.title);
+    this.add(notification);
+  }
+};
+
+
+/**
+ * A basic notification.  Subclass this to create more complex notifications.
+ */
+this.Notification =
+ function Notification(title, description, iconURL, priority, buttons) {
+  this.title = title;
+  this.description = description;
+
+  if (iconURL)
+    this.iconURL = iconURL;
+
+  if (priority)
+    this.priority = priority;
+
+  if (buttons)
+    this.buttons = buttons;
+}
+
+// We set each prototype property individually instead of redefining
+// the entire prototype to avoid blowing away existing properties
+// of the prototype like the the "constructor" property, which we use
+// to bind notification objects to their XBL representations.
+Notification.prototype.priority = Notifications.PRIORITY_INFO;
+Notification.prototype.iconURL = null;
+Notification.prototype.buttons = [];
+
+/**
+ * A button to display in a notification.
+ */
+this.NotificationButton =
+ function NotificationButton(label, accessKey, callback) {
+  function callbackWrapper() {
+    try {
+      callback.apply(this, arguments);
+    } catch (e) {
+      let logger = Log.repository.getLogger("Sync.Notifications");
+      logger.error("An exception occurred: " + Utils.exceptionStr(e));
+      logger.info(Utils.stackTrace(e));
+      throw e;
+    }
+  }
+
+  this.label = label;
+  this.accessKey = accessKey;
+  this.callback = callbackWrapper;
+}