add unit tests for status filter predicate

mastodon/src/main/java/org/joinmastodon/android/model/Status.java

@@ -50,6 +50,8 @@ public class Status extends BaseModel implements DisplayItemsParent, Searchable{
 	public long favouritesCount;
 	public long repliesCount;
 	public Instant editedAt;
+	// might not be provided (by older mastodon servers),
+	// so megalodon will use the locally cached filters if filtered == null
 	public List<FilterResult> filtered;
 
 	public String url;
@@ -180,7 +182,6 @@ public class Status extends BaseModel implements DisplayItemsParent, Searchable{
 		s.mentions = List.of();
 		s.tags = List.of();
 		s.emojis = List.of();
-		s.filtered = List.of();
 		return s;
 	}