question: 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 ; } }
target:  Creates a new instance.