[#11930] Non-Youtube URLs should be ignored

Author: tfga

app/src/main/java/org/schabi/newpipe/local/playlist/LocalPlaylistFragment.java

@@ -65,6 +65,7 @@
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
+import java.util.Objects;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
@@ -461,6 +462,7 @@ static String exportAsYoutubeTempPlaylist(final Stream<StreamEntity> entityStrea
 
         final String videoIDs = entityStream
                 .map(entity -> getYouTubeId(entity.getUrl()))
+                .filter(Objects::nonNull)
                 .collect(Collectors.joining(","));
 
         return "http://www.youtube.com/watch_videos?video_ids=" + videoIDs;

app/src/test/java/org/schabi/newpipe/local/playlist/LocalPlaylistFragmentTest.java

@@ -20,7 +20,8 @@ public void exportAsYouTubeTempPlaylist() {
         final Stream<StreamEntity> entityStream = asStreamEntityStream(
 
             "https://www.youtube.com/watch?v=1",
-            "https://www.youtube.com/watch?v=2",
+            "https://soundcloud.com/cautious-clayofficial/cold-war-2", // non-Youtube URLs should be
+            "https://www.youtube.com/watch?v=2",                       // ignored
             "https://www.youtube.com/watch?v=3"
         );