public synchronized void changeSettings(@NotNull NotificationSettings settings) {
    String groupDisplayName = settings.getGroupId();
    if (settings.equals(getDefaultSettings(groupDisplayName))) {
      myIdToSettingsMap.remove(groupDisplayName);
    }
    else {
      myIdToSettingsMap.put(groupDisplayName, settings);
    }
  }
public synchronized void changeSettings(@NotNull NotificationSettings settings)