[mtv] Add support for urls from the mobile site (fixes #1959)

youtube_dl/extractor/mtv.py

@@ -93,7 +93,9 @@ class MTVServicesInfoExtractor(InfoExtractor):
 
 
 class MTVIE(MTVServicesInfoExtractor):
-    _VALID_URL = r'^https?://(?:www\.)?mtv\.com/videos/.+?/(?P<videoid>[0-9]+)/[^/]+$'
+    _VALID_URL = r'''(?x)^https?://
+        (?:(?:www\.)?mtv\.com/videos/.+?/(?P<videoid>[0-9]+)/[^/]+$|
+           m\.mtv\.com/videos/video\.rbml\?.*?id=(?P<mgid>[^&]+))'''
 
     _FEED_URL = 'http://www.mtv.com/player/embed/AS3/rss/'
 
@@ -127,7 +129,8 @@ class MTVIE(MTVServicesInfoExtractor):
     def _real_extract(self, url):
         mobj = re.match(self._VALID_URL, url)
         video_id = mobj.group('videoid')
-
+        uri = mobj.group('mgid')
+        if uri is None:
             webpage = self._download_webpage(url, video_id)
     
             # Some videos come from Vevo.com