diff -r 000000000000 -r 6474c204b198 addon-sdk/source/lib/sdk/window/events.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/addon-sdk/source/lib/sdk/window/events.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,46 @@
+/* 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/. */
+"use strict";
+
+module.metadata = {
+  "stability": "unstable"
+};
+
+const { Ci } = require("chrome");
+const { observe } = require("../event/chrome");
+const { open } = require("../event/dom");
+const { windows } = require("../window/utils");
+const { filter, merge, map, expand } = require("../event/utils");
+
+// Function registers single shot event listeners for relevant window events
+// that forward events to exported event stream.
+function eventsFor(window) {
+  let interactive = open(window, "DOMContentLoaded", { capture: true });
+  let complete = open(window, "load", { capture: true });
+  let states = merge([interactive, complete]);
+  let changes = filter(states, function({target}) target === window.document);
+  return map(changes, function({type, target}) {
+    return { type: type, target: target.defaultView }
+  });
+}
+
+// In addition to observing windows that are open we also observe windows
+// that are already already opened in case they're in process of loading.
+let opened = windows(null, { includePrivate: true });
+let currentEvents = merge(opened.map(eventsFor));
+
+// Register system event listeners for top level window open / close.
+function rename({type, target, data}) {
+  return { type: rename[type], target: target, data: data }
+}
+rename.domwindowopened = "open";
+rename.domwindowclosed = "close";
+
+let openEvents = map(observe("domwindowopened"), rename);
+let closeEvents = map(observe("domwindowclosed"), rename);
+let futureEvents = expand(openEvents, function({target}) eventsFor(target));
+
+let channel = merge([currentEvents, futureEvents,
+                     openEvents, closeEvents]);
+exports.events = channel;