diff -r 000000000000 -r 6474c204b198 toolkit/components/places/tests/unit/nsDummyObserver.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolkit/components/places/tests/unit/nsDummyObserver.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,53 @@
+/* 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/. */
+
+Components.utils.import("resource://gre/modules/XPCOMUtils.jsm");
+
+const Cc = Components.classes;
+const Ci = Components.interfaces;
+
+// Dummy boomark/history observer
+function DummyObserver() {
+  let os = Cc["@mozilla.org/observer-service;1"].
+           getService(Ci.nsIObserverService);
+  os.notifyObservers(null, "dummy-observer-created", null);
+}
+
+DummyObserver.prototype = {
+  // history observer
+  onBeginUpdateBatch: function () {},
+  onEndUpdateBatch: function () {},
+  onVisit: function (aURI, aVisitID, aTime, aSessionID, aReferringID, aTransitionType) {
+    let os = Cc["@mozilla.org/observer-service;1"].
+             getService(Ci.nsIObserverService);
+    os.notifyObservers(null, "dummy-observer-visited", null);
+  },
+  onTitleChanged: function () {},
+  onDeleteURI: function () {},
+  onClearHistory: function () {},
+  onPageChanged: function () {},
+  onDeleteVisits: function () {},
+
+  // bookmark observer
+  //onBeginUpdateBatch: function() {},
+  //onEndUpdateBatch: function() {},
+  onItemAdded: function(aItemId, aParentId, aIndex, aItemType, aURI) {
+    let os = Cc["@mozilla.org/observer-service;1"].
+             getService(Ci.nsIObserverService);
+    os.notifyObservers(null, "dummy-observer-item-added", null);
+  },
+  onItemChanged: function () {},
+  onItemRemoved: function() {},
+  onItemVisited: function() {},
+  onItemMoved: function() {},
+
+  classID: Components.ID("62e221d3-68c3-4e1a-8943-a27beb5005fe"),
+
+  QueryInterface: XPCOMUtils.generateQI([
+    Ci.nsINavBookmarkObserver,
+    Ci.nsINavHistoryObserver,
+  ])
+};
+
+this.NSGetFactory = XPCOMUtils.generateNSGetFactory([DummyObserver]);