[kickstarter] Simplify and fix test case

youtube_dl/extractor/kickstarter.py

@@ -1,8 +1,6 @@
 # encoding: utf-8
 from __future__ import unicode_literals
 
-import re
-
 from .common import InfoExtractor
 
 
@@ -21,8 +19,6 @@ class KickStarterIE(InfoExtractor):
     }, {
         'note': 'Embedded video (not using the native kickstarter video service)',
         'url': 'https://www.kickstarter.com/projects/597507018/pebble-e-paper-watch-for-iphone-and-android/posts/659178',
-        'playlist': [
-            {
         'info_dict': {
             'id': '78704821',
             'ext': 'mp4',
@@ -30,13 +26,10 @@ class KickStarterIE(InfoExtractor):
             'uploader': 'Pebble Technology',
             'title': 'Pebble iOS Notifications',
         }
-            }
-        ],
     }]
 
     def _real_extract(self, url):
-        m = re.match(self._VALID_URL, url)
-        video_id = m.group('id')
+        video_id = self._match_id(url)
         webpage = self._download_webpage(url, video_id)
 
         title = self._html_search_regex(