@Override
  protected void finalize() throws Throwable {
    super.finalize();

    /** Mozilla: Not needed for the application. */
    mPackageMonitor.unregister();
  }
  /**
   * Creates a new instance.
   *
   * @param context Context for loading resources.
   * @param historyFileName The history XML file.
   */
  private ActivityChooserModel(Context context, String historyFileName) {
    mContext = context.getApplicationContext();
    if (!TextUtils.isEmpty(historyFileName) && !historyFileName.endsWith(HISTORY_FILE_EXTENSION)) {
      mHistoryFileName = historyFileName + HISTORY_FILE_EXTENSION;
    } else {
      mHistoryFileName = historyFileName;
    }

    /** Mozilla: Uses modified receiver */
    mPackageMonitor.register(mContext);
  }