RSS: Correctly clean up config file when removing a feed

src/rss/rssfeed.cpp

@@ -113,6 +113,11 @@ void RssFeed::removeAllSettings() {
     all_feeds_filters.remove(m_url);
     qBTRSS.setValue("feed_filters", all_feeds_filters);
   }
+  QHash<QString, QVariant> all_old_items = qBTRSS.value("old_items", QHash<QString, QVariant>()).toHash();
+  if (all_old_items.contains(m_url)) {
+      all_old_items.remove(m_url);
+      qBTRSS.setValue("old_items", all_old_items);
+  }
 }
 
 bool RssFeed::itemAlreadyExists(const QString &hash) const {