[YouTube] Music Mix: Fix playlist not being accepted

Regression introduced by YouTube Mix support (#280)

Author: TobiGr

extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/YoutubeParsingHelper.java

@@ -205,12 +205,12 @@ public static boolean isYoutubeMixId(final String playlistId) {
 
     /**
      * Checks if the given playlist id is a YouTube Music Mix (auto-generated playlist)
-     * Ids from a YouTube Music Mix start with "RDAMVM"
+     * Ids from a YouTube Music Mix start with "RDAMVM" or "RDCLAK"
      * @param playlistId
      * @return Whether given id belongs to a YouTube Music Mix
      */
     public static boolean isYoutubeMusicMixId(final String playlistId) {
-        return playlistId.startsWith("RDAMVM");
+        return playlistId.startsWith("RDAMVM") || playlistId.startsWith("RDCLAK");
     }
     /**
      * Checks if the given playlist id is a YouTube Channel Mix (auto-generated playlist)
@@ -229,7 +229,7 @@ public static String extractVideoIdFromMixId(final String playlistId) throws Par
         if (playlistId.startsWith("RDMM")) { //My Mix
             return playlistId.substring(4);
 
-        } else if (playlistId.startsWith("RDAMVM")) { //Music mix
+        } else if (playlistId.startsWith("RDAMVM") || playlistId.startsWith("RDCLAK")) { //Music mix
             return playlistId.substring(6);
 
         } else if (playlistId.startsWith("RMCM")) { //Channel mix

extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/YoutubeService.java

@@ -111,7 +111,8 @@ public ChannelExtractor getChannelExtractor(ListLinkHandler linkHandler) {
 
     @Override
     public PlaylistExtractor getPlaylistExtractor(final ListLinkHandler linkHandler) {
-        if (YoutubeParsingHelper.isYoutubeMixId(linkHandler.getId())) {
+        if (YoutubeParsingHelper.isYoutubeMixId(linkHandler.getId())
+                && !YoutubeParsingHelper.isYoutubeMusicMixId(linkHandler.getId())) {
             return new YoutubeMixPlaylistExtractor(this, linkHandler);
         } else {
             return new YoutubePlaylistExtractor(this, linkHandler);

extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/linkHandler/YoutubePlaylistLinkHandlerFactory.java

@@ -52,11 +52,6 @@ public String getId(final String url) throws ParsingException {
                         "the list-ID given in the URL does not match the list pattern");
             }
 
-            if (YoutubeParsingHelper.isYoutubeMusicMixId(listID)) {
-                throw new ContentNotSupportedException(
-                        "YouTube Music Mix playlists are not yet supported");
-            }
-
             if (YoutubeParsingHelper.isYoutubeChannelMixId(listID)
                     && Utils.getQueryValue(urlObj, "v") == null) {
                 //Video id can't be determined from the channel mix id. See YoutubeParsingHelper#extractVideoIdFromMixId