Bug 148755 Add tthe status to the ActivityStackEvent.
If the the event rollback, the ActivityStackEvent status should be ROLL_BACK.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/activity/ActivityStack.java
/**
	 * Returns the label of the record at the top of the redo stack. The label
	 * describes the next operation to be redone.
	 * 
	 * @return The redo label, or null if there is no record to be redone.
	 */
	public String getRedoLabel( )
	{
		IActivityRecord cmd = getRedoRecord( );
		if ( cmd == null )
			return null;
		
		
		String label = cmd.getLabel( );
		assert label != null;
		return label;
	}
	/**
	 * Starts a transaction. All calls to execute( ) add records to the active
	 * transactions. Transactions can nest. Calls to undo( ) or redo( ) are
	 * illegal until the transaction completes. The compound record uses a
	 * generic label.
	 */
	public void startTrans( )
	{
		startTrans( null );
	}
	/**
	 * Starts a transaction. The application provides the message ID for a label
	 * to associate with the transaction.