Record that MediaStream creates MediaStreamTracks

tools/dom/scripts/dartmetadata.py

 #!/usr/bin/python
 # Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 
 """This module provides shared functionality to provide Dart metadata for
 DOM APIs.
 """
 
 import copy
@@ skipping 237 matching lines @@
       "@Creates('int|String|Null')",
       "@Returns('int|String|Null')",
     ],
 
     'ImageData.data': [
       "@Creates('NativeUint8ClampedList')",
       "@Returns('NativeUint8ClampedList')",
     ],
 
     'MediaStream.getAudioTracks': [
-      "@Creates('JSExtendableArray')",
+      "@Creates('JSExtendableArray|MediaStreamTrack')",
       "@Returns('JSExtendableArray')",
     ],
 
     'MediaStream.getVideoTracks': [
-      "@Creates('JSExtendableArray')",
+      "@Creates('JSExtendableArray|MediaStreamTrack')",

[Alan Knight, 2016/07/19 23:42:21]

The IDL says this returns sequence<MediaStreamTrack>. Is it true that it can
return an individual track?

I also wonder if there's a reason we have to specify these here, or if it's
historical and if we deleted the entry entirely what it would generate for that
IDL.

       "@Returns('JSExtendableArray')",
     ],
 
     'MessageEvent.data': [
       "@annotation_Creates_SerializedScriptValue",
       "@annotation_Returns_SerializedScriptValue",
     ],
 
     'MessageEvent.ports': ["@Creates('JSExtendableArray')"],
 
@@ skipping 613 matching lines @@
       pass
     else:
       _logger.warn('Unknown support_level - %s:%s' % (interface_id, member_id))
 
     return annotations
 
   def Flush(self):
     json_file = open(self._api_status_path, 'w+')
     json.dump(self._types, json_file, indent=2, separators=(',', ': '), sort_keys=True)
     json_file.close()