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diff --git a/toolkit/jetpack/sdk/core/promise.js b/toolkit/jetpack/sdk/core/promise.js
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+/* 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';
+
+/*
+ * Uses `Promise.jsm` as a core implementation, with additional sugar
+ * from previous implementation, with inspiration from `Q` and `when`
+ *
+ * https://developer.mozilla.org/en-US/docs/Mozilla/JavaScript_code_modules/Promise.jsm
+ * https://github.com/cujojs/when
+ * https://github.com/kriskowal/q
+ */
+const PROMISE_URI = 'resource://gre/modules/Promise.jsm';
+
+getEnvironment.call(this, function ({ require, exports, module, Cu }) {
+
+const Promise = Cu.import(PROMISE_URI, {}).Promise;
+const { Debugging, defer, resolve, all, reject, race } = Promise;
+
+module.metadata = {
+  'stability': 'unstable'
+};
+
+var promised = (function() {
+  // Note: Define shortcuts and utility functions here in order to avoid
+  // slower property accesses and unnecessary closure creations on each
+  // call of this popular function.
+
+  var call = Function.call;
+  var concat = Array.prototype.concat;
+
+  // Utility function that does following:
+  // execute([ f, self, args...]) => f.apply(self, args)
+  function execute (args) {
+    return call.apply(call, args);
+  }
+
+  // Utility function that takes promise of `a` array and maybe promise `b`
+  // as arguments and returns promise for `a.concat(b)`.
+  function promisedConcat(promises, unknown) {
+    return promises.then(function (values) {
+      return resolve(unknown)
+        .then(value => values.concat([value]));
+    });
+  }
+
+  return function promised(f, prototype) {
+    /**
+    Returns a wrapped `f`, which when called returns a promise that resolves to
+    `f(...)` passing all the given arguments to it, which by the way may be
+    promises. Optionally second `prototype` argument may be provided to be used
+    a prototype for a returned promise.
+
+    ## Example
+
+    var promise = promised(Array)(1, promise(2), promise(3))
+    promise.then(console.log) // => [ 1, 2, 3 ]
+    **/
+
+    return function promised(...args) {
+      // create array of [ f, this, args... ]
+      return [f, this, ...args].
+        // reduce it via `promisedConcat` to get promised array of fulfillments
+        reduce(promisedConcat, resolve([], prototype)).
+        // finally map that to promise of `f.apply(this, args...)`
+        then(execute);
+    };
+  };
+})();
+
+exports.promised = promised;
+exports.all = all;
+exports.defer = defer;
+exports.resolve = resolve;
+exports.reject = reject;
+exports.race = race;
+exports.Promise = Promise;
+exports.Debugging = Debugging;
+});
+
+function getEnvironment (callback) {
+  let Cu, _exports, _module, _require;
+
+  // CommonJS / SDK
+  if (typeof(require) === 'function') {
+    Cu = require('chrome').Cu;
+    _exports = exports;
+    _module = module;
+    _require = require;
+  }
+  // JSM
+  else if (String(this).indexOf('BackstagePass') >= 0) {
+    Cu = this['Components'].utils;
+    _exports = this.Promise = {};
+    _module = { uri: __URI__, id: 'promise/core' };
+    _require = uri => {
+      let imports = {};
+      Cu.import(uri, imports);
+      return imports;
+    };
+    this.EXPORTED_SYMBOLS = ['Promise'];
+  // mozIJSSubScriptLoader.loadSubscript
+  } else if (~String(this).indexOf('Sandbox')) {
+    Cu = this['Components'].utils;
+    _exports = this;
+    _module = { id: 'promise/core' };
+    _require = uri => {};
+  }
+
+  callback({
+    Cu: Cu,
+    exports: _exports,
+    module: _module,
+    require: _require
+  });
+}
+