diff -r 000000000000 -r 6474c204b198 dom/webidl/Promise.webidl
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dom/webidl/Promise.webidl	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,47 @@
+/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 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/.
+ *
+ * The origin of this IDL file is
+ * http://dom.spec.whatwg.org/#promises
+ */
+
+// TODO We use object instead Function.  There is an open issue on WebIDL to
+// have different types for "platform-provided function" and "user-provided
+// function"; for now, we just use "object".
+callback PromiseInit = void (object resolve, object reject);
+
+[TreatNonCallableAsNull]
+callback AnyCallback = any (any value);
+
+// REMOVE THE RELEVANT ENTRY FROM test_interfaces.html WHEN THIS IS IMPLEMENTED IN JS.
+[Constructor(PromiseInit init)]
+interface Promise {
+  // TODO bug 875289 - static Promise fulfill(any value);
+
+  // Disable the static methods when the interface object is supposed to be
+  // disabled, just in case some code decides to walk over to .constructor from
+  // the proto of a promise object or someone screws up and manages to create a
+  // Promise object in this scope without having resolved the interface object
+  // first.
+  [NewObject, Throws]
+  static Promise resolve(optional any value);
+  [NewObject, Throws]
+  static Promise reject(optional any value);
+
+  // The [TreatNonCallableAsNull] annotation is required since then() should do
+  // nothing instead of throwing errors when non-callable arguments are passed.
+  [NewObject]
+  Promise then([TreatNonCallableAsNull] optional AnyCallback? fulfillCallback = null,
+               [TreatNonCallableAsNull] optional AnyCallback? rejectCallback = null);
+
+  [NewObject]
+  Promise catch([TreatNonCallableAsNull] optional AnyCallback? rejectCallback = null);
+
+  [NewObject, Throws]
+  static Promise all(sequence<any> iterable);
+
+  [NewObject, Throws]
+  static Promise race(sequence<any> iterable);
+};