Fix the deletion of torrents when using the context menu of the label sidepanel.

It now uses the same logic as the code that deletes torrents when using the context menu of the transferlist.
Closes #2729.

src/gui/transferlistwidget.cpp

@@ -328,16 +328,16 @@ void TransferListWidget::deleteSelectedTorrents()
 void TransferListWidget::deleteVisibleTorrents()
 {
     if (nameFilterModel->rowCount() <= 0) return;
-    QTorrentHandle torrent = BTSession->getTorrentHandle(getHashFromRow(0));
-    bool delete_local_files = false;
-    if (Preferences::instance()->confirmTorrentDeletion() &&
-        !DeletionConfirmationDlg::askForDeletionConfirmation(delete_local_files, nameFilterModel->rowCount(), torrent.name()))
-        return;
     QStringList hashes;
     for (int i = 0; i<nameFilterModel->rowCount(); ++i) {
         const int row = mapToSource(nameFilterModel->index(i, 0)).row();
         hashes << getHashFromRow(row);
     }
+    QTorrentHandle torrent = BTSession->getTorrentHandle(hashes[0]);
+    bool delete_local_files = false;
+    if (Preferences::instance()->confirmTorrentDeletion() &&
+        !DeletionConfirmationDlg::askForDeletionConfirmation(delete_local_files, hashes.size(), torrent.name()))
+        return;
     foreach (const QString &hash, hashes)
         BTSession->deleteTorrent(hash, delete_local_files);
 }