[downloader/dash] Rename the protocol

'http_dash_segments' looks more like a protocol name than
'dash_segments'

youtube_dl/downloader/__init__.py

@@ -21,7 +21,7 @@ PROTOCOL_MAP = {
     'mms': RtspFD,
     'rtsp': RtspFD,
     'f4m': F4mFD,
-    'dash_segments': DashSegmentsFD,
+    'http_dash_segments': DashSegmentsFD,
 }
 
 

youtube_dl/extractor/youtube.py

@@ -820,7 +820,7 @@ class YoutubeIE(YoutubeBaseInfoExtractor):
                         f.update({
                             'initialization_url': segment_list.find('{urn:mpeg:DASH:schema:MPD:2011}Initialization').attrib['sourceURL'],
                             'segment_urls': [segment.attrib.get('media') for segment in segment_list.findall('{urn:mpeg:DASH:schema:MPD:2011}SegmentURL')],
-                            'protocol': 'dash_segments',
+                            'protocol': 'http_dash_segments',
                         })
                     try:
                         existing_format = next(