Add getThumbnailUrl() to PlaylistLocalItem interface

Co-authored-by: Haggai Eran <haggai.eran@gmail.com>

Author: Stypox

app/src/main/java/org/schabi/newpipe/database/playlist/PlaylistLocalItem.java

@@ -1,5 +1,7 @@
 package org.schabi.newpipe.database.playlist;
 
+import androidx.annotation.Nullable;
+
 import org.schabi.newpipe.database.LocalItem;
 
 public interface PlaylistLocalItem extends LocalItem {
@@ -10,4 +12,7 @@ public interface PlaylistLocalItem extends LocalItem {
     long getUid();
 
     void setDisplayIndex(long displayIndex);
+
+    @Nullable
+    String getThumbnailUrl();
 }

app/src/main/java/org/schabi/newpipe/database/playlist/PlaylistMetadataEntry.java

@@ -9,6 +9,8 @@
 import static org.schabi.newpipe.database.playlist.model.PlaylistEntity.PLAYLIST_THUMBNAIL_STREAM_ID;
 import static org.schabi.newpipe.database.playlist.model.PlaylistEntity.PLAYLIST_THUMBNAIL_URL;
 
+import androidx.annotation.Nullable;
+
 public class PlaylistMetadataEntry implements PlaylistLocalItem {
     public static final String PLAYLIST_STREAM_COUNT = "streamCount";
 
@@ -71,4 +73,10 @@ public long getUid() {
     public void setDisplayIndex(final long displayIndex) {
         this.displayIndex = displayIndex;
     }
+
+    @Nullable
+    @Override
+    public String getThumbnailUrl() {
+        return thumbnailUrl;
+    }
 }

app/src/main/java/org/schabi/newpipe/database/playlist/model/PlaylistRemoteEntity.java

@@ -2,6 +2,7 @@
 
 import android.text.TextUtils;
 
+import androidx.annotation.Nullable;
 import androidx.room.ColumnInfo;
 import androidx.room.Entity;
 import androidx.room.Ignore;
@@ -134,6 +135,8 @@ public void setName(final String name) {
         this.name = name;
     }
 
+    @Nullable
+    @Override
     public String getThumbnailUrl() {
         return thumbnailUrl;
     }