diff -r 000000000000 -r 6474c204b198 toolkit/components/jsdownloads/test/unit/tail.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolkit/components/jsdownloads/test/unit/tail.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,25 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=2 et sw=2 tw=80: */
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/**
+ * Provides infrastructure for automated download components tests.
+ */
+
+"use strict";
+
+////////////////////////////////////////////////////////////////////////////////
+//// Termination functions common to all tests
+
+add_task(function test_common_terminate()
+{
+  // Ensure all the pending HTTP requests have a chance to finish.
+  continueResponses();
+
+  // Stop the HTTP server.  We must do this inside a task in "tail.js" until the
+  // xpcshell testing framework supports asynchronous termination functions.
+  let deferred = Promise.defer();
+  gHttpServer.stop(deferred.resolve);
+  yield deferred.promise;
+});