During upgrade to the Chromium 61 we have switched from GTK2 to GTK3
and now we have a few warnings about stuff being deprecated in GTK3.
Check any Linux build to get a list of them.

/cc @zcbenz 
atom/browser/ui/file_dialog_gtk.cc
std::vector<base::FilePath>* paths) {
  GtkFileChooserAction action = GTK_FILE_CHOOSER_ACTION_OPEN;
  if (settings.properties & FILE_DIALOG_OPEN_DIRECTORY)
    action = GTK_FILE_CHOOSER_ACTION_SELECT_FOLDER;
  FileChooserDialog open_dialog(action, settings);
  open_dialog.SetupProperties(settings.properties);
  gtk_widget_show_all(open_dialog.dialog());
  int response = gtk_dialog_run(GTK_DIALOG(open_dialog.dialog()));
  if (response == GTK_RESPONSE_ACCEPT) {
    *paths = open_dialog.GetFileNames();
    return true;
  } else {
    return false;
  }
}
void ShowOpenDialog(const DialogSettings& settings,