/**
  * Adds a historical record.
  *
  * @param historicalRecord The record to add.
  * @return True if the record was added.
  */
 private boolean addHistoricalRecord(HistoricalRecord historicalRecord) {
   final boolean added = mHistoricalRecords.add(historicalRecord);
   if (added) {
     mHistoricalRecordsChanged = true;
     pruneExcessiveHistoricalRecordsIfNeeded();
     persistHistoricalDataIfNeeded();
     sortActivitiesIfNeeded();
     notifyChanged();
   }
   return added;
 }
  /**
   * Removes all historical records for this pkg.
   *
   * @param historicalRecord The pkg to delete records for.
   * @return True if the record was added.
   */
  boolean removeHistoricalRecordsForPackage(final String pkg) {
    boolean removed = false;

    for (Iterator<HistoricalRecord> i = mHistoricalRecords.iterator(); i.hasNext(); ) {
      final HistoricalRecord record = i.next();
      if (record.activity.getPackageName().equals(pkg)) {
        i.remove();
        removed = true;
      }
    }

    if (removed) {
      mHistoricalRecordsChanged = true;
      pruneExcessiveHistoricalRecordsIfNeeded();
      persistHistoricalDataIfNeeded();
      sortActivitiesIfNeeded();
      notifyChanged();
    }

    return removed;
  }