Revert "[extractor/generic] Make _search_json_ld non fatal"

This reverts commit 958849275f.

youtube_dl/extractor/generic.py

@@ -2241,7 +2241,7 @@ class GenericIE(InfoExtractor):
 
         # Looking for http://schema.org/VideoObject
         json_ld = self._search_json_ld(
-            webpage, video_id, fatal=False, expected_type='VideoObject')
+            webpage, video_id, default=None, expected_type='VideoObject')
         if json_ld and json_ld.get('url'):
             info_dict.update({
                 'title': video_title or info_dict['title'],