Replace buggy Promise polyfill

A bug in our Promise polyfill caused issues with the recently-added
AbortableOperation class on IE11.  Since external polyfills for this
are smaller, it is easier to remove ours in favor of a third-party
polyfill.  Applications that wish to support IE11 must now load this
additional polyfill.

We are using the "es6-promise-polyfill" module from npm, but any
compliant polyfill should suffice.

One feature our own polyfill offered was the ability to flush all
Promises, which allowed us to write synchronous unit tests that
simulated async processes.  To get this ability back, we are now
using the "promise-mock" module in our tests.

Getting "promise-mock" to load correctly involved switching from
"requirejs" to "cajon", which builds on requirejs and supports
AMD modules more directly.

Closes #1260

Change-Id: I5de48e88a910736ae5c1897a7a509bc5641acb70

Author: joeyparrish

README.md

@@ -40,10 +40,12 @@ NOTES:
  - ¹: Only the latest stable version is tested and supported. Older releases may still be usable, and we will accept pull requests for them, but they will not be officially tested or supported.
  - ²: Latest stable Chromecast firmware is tested. Both sender and receiver can be implemented with Shaka Player.
  - ³: Tizen 2017 model is actively tested and supported by the Shaka Player team. Tizen 2016 model is community-supported and untested by us.
- - ⁴: IE 11 offers PlayReady support on Windows 8.1 and Windows 10 only. IE 11 can play clear content on Windows 8.0. IE 11 does not support adaptive playback on Windows 7 and under.
+ - ⁴: IE 11 offers PlayReady support on Windows 8.1 and Windows 10 only. IE 11 can play clear content on Windows 8.0. IE 11 does not support adaptive playback on Windows 7 and under. A separate [Promise polyfill][] is required for IE 11.
  - ⁵: These are expected to work, but are not actively tested by the Shaka Player team.
  - ⁶: All iOS browers use the same HTML engine (Apple WebKit) and are not supported because they lack MediaSource support. For more information, see: https://github.com/google/shaka-player/issues/997
 
+[Promise polyfill]: https://github.com/lahmatiy/es6-promise-polyfill
+
 
 ## Manifest format support matrix
 

build/types/polyfill

@@ -9,7 +9,6 @@
 +../../lib/polyfill/patchedmediakeys_ms.js
 +../../lib/polyfill/patchedmediakeys_nop.js
 +../../lib/polyfill/patchedmediakeys_webkit.js
-+../../lib/polyfill/promise.js
 +../../lib/polyfill/video_play_promise.js
 +../../lib/polyfill/videoplaybackquality.js
 +../../lib/polyfill/vttcue.js

demo/index.html

@@ -36,7 +36,10 @@
     <link rel="stylesheet" href="https://fonts.googleapis.com/icon?family=Material+Icons">
 
     <script defer src="//www.gstatic.com/cv/js/sender/v1/cast_sender.js"></script>
+    <!-- transmuxing support is enabled by including this: -->
     <script defer src="../node_modules/mux.js/dist/mux.js"></script>
+    <!-- IE11 support is enabled by including this: -->
+    <script defer src="../node_modules/es6-promise-polyfill/promise.min.js"></script>
 
     <script>
 COMPILED_JS = [

docs/tutorials/faq.md

@@ -136,6 +136,18 @@ existing http plugin for `file://` requests:
 shaka.net.NetworkingEngine.registerScheme('file', shaka.net.HttpPlugin);
 ```
 
+<hr>
+
+**Q:** Why doesn't my app work in IE 11?
+
+**A:** IE 11 doesn't have native Promise support.  Starting with v2.4,
+applications are required to load their own Promise polyfill for IE support.
+We no longer maintain and ship our own polyfill for this.  We recommend
+es6-promise-polyfill.
+
+Polyfill source: https://github.com/lahmatiy/es6-promise-polyfill
+Polyfill on NPM: https://www.npmjs.com/package/es6-promise-polyfill
+
 
 [386]: https://github.com/google/shaka-player/issues/386#issuecomment-227898001
 [489]: https://github.com/google/shaka-player/issues/489#issuecomment-240466224

docs/tutorials/plugins.md

@@ -69,7 +69,6 @@ __Polyfills__
       {@linksource shaka.polyfill.VideoPlaybackQuality}
     - prefixed EME implementations for IE 11 and very old versions of embedded
       Chrome/Chromium: {@linksource shaka.polyfill.MediaKeys}
-    - Promise implementation for IE 11: {@linksource shaka.polyfill.Promise}
     - variants of VTTCue and TextTrackCue constructors:
       {@linksource shaka.polyfill.VTTCue}
 

karma.conf.js

@@ -82,17 +82,14 @@ module.exports = function(config) {
       'dist/deps.js',
       'shaka-player.uncompiled.js',
 
-      // sprintf module next
-      // Since we don't use require to load the sprintf module, this must be
-      // loaded before requirejs is loaded!  Otherwise, it tries to use
-      // requirejs instead of loading directly into the window.
-      'node_modules/sprintf-js/src/sprintf.js',
+      // Promise polyfill for IE11 and some older TVs
+      'node_modules/es6-promise-polyfill/promise.js',
 
       // muxjs module next
       'node_modules/mux.js/dist/mux.js',
 
-      // requirejs module next
-      'node_modules/requirejs/require.js',
+      // cajon module (an AMD variant of requirejs) next
+      'node_modules/cajon/cajon.js',
 
       // bootstrapping for the test suite
       'test/test/boot.js',
@@ -113,6 +110,7 @@ module.exports = function(config) {
       {pattern: 'third_party/closure/goog/**/*.js', included: false},
       {pattern: 'test/test/assets/*', included: false},
       {pattern: 'dist/shaka-player.compiled.js', included: false},
+      {pattern: 'node_modules/**/*.js', included: false},
     ],
 
     // NOTE: Do not use proxies at all!  They cannot be used with the --hostname