message: Fix cannot copy file to a empty folder in file browser.
diff: @@ -1113,7 +1113,7 @@ void FileBrowserDialog::updateTable(const QList<SeafDirent>& dirents)
  {
  if (dirents.isEmpty()) {
  table_model_->setDirents(QList<SeafDirent>());
  - stack_->setCurrentIndex(INDEX_EMPTY_VIEW);
  + stack_->setCurrentIndex(INDEX_TABLE_VIEW);
  } else {
  table_model_->setDirents(dirents);
  stack_->setCurrentIndex(INDEX_TABLE_VIEW);
  @@ -1337,7 +1337,7 @@ void FileBrowserDialog::onDirentRemoveSuccess(const QString& path)
  updateFileCount();
  if (table_model_->rowCount() == 0) {
  - stack_->setCurrentIndex(INDEX_EMPTY_VIEW);
  + stack_->setCurrentIndex(INDEX_TABLE_VIEW);
  }
  }
  @@ -1359,7 +1359,7 @@ void FileBrowserDialog::onDirentsRemoveSuccess(const QString& parent_path,
  updateFileCount();
  if (table_model_->rowCount() == 0) {
  - stack_->setCurrentIndex(INDEX_EMPTY_VIEW);
  + stack_->setCurrentIndex(INDEX_TABLE_VIEW);
  }
  }
  