Prevent NullRef on CustomFormat parse

src/NzbDrone.Core/CustomFormats/CustomFormatCalculationService.cs

@@ -93,8 +93,12 @@ namespace NzbDrone.Core.CustomFormats
         }
 
         public List<CustomFormat> ParseCustomFormat(ParsedEpisodeInfo episodeInfo, Series series)
+        {
+            if (series?.OriginalLanguage != null)
             {
                 episodeInfo.ExtraInfo["OriginalLanguage"] = series.OriginalLanguage;
+            }
+
             return ParseCustomFormat(episodeInfo, _formatService.All());
         }