Set the playlist_index and playlist fields for already resolved video results.

youtube_dl/YoutubeDL.py

@@ -348,6 +348,7 @@ class YoutubeDL(object):
 
         result_type = ie_result.get('_type', 'video') # If not given we suppose it's a video, support the default old system
         if result_type == 'video':
+            ie_result.update(extra_info)
             if 'playlist' not in ie_result:
                 # It isn't part of a playlist
                 ie_result['playlist'] = None

youtube_dl/extractor/steam.py

@@ -23,14 +23,16 @@ class SteamIE(InfoExtractor):
                 u"file": u"81300.flv",
                 u"md5": u"f870007cee7065d7c76b88f0a45ecc07",
                 u"info_dict": {
-                        u"title": u"Terraria 1.1 Trailer"
+                        u"title": u"Terraria 1.1 Trailer",
+                        u'playlist_index': 1,
                 }
             },
             {
                 u"file": u"80859.flv",
                 u"md5": u"61aaf31a5c5c3041afb58fb83cbb5751",
                 u"info_dict": {
-                    u"title": u"Terraria Trailer"
+                    u"title": u"Terraria Trailer",
+                    u'playlist_index': 2,
                 }
             }
         ]