Bug 132805 Set descending to outer group will affect inner group.
Description: Set descending to outer group will affect inner group. Steps to reproduce: 1. New a sample datasource and dataset from orders. 2. Drag the dataset to Layout. 3. Add a group on ordernumber, interval 10, descending. 4. Add another group on orderdate, interval day 2, ascending. 5. Preview. Expected result: Data are grouped correctly. Actual result: Inner group didn't work unless you set outer group's sort to asc.
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/impl/QueryExecutorUtil.java
dest.setName( src.getName() );
		dest.setInterval( src.getInterval());
		dest.setIntervalRange( src.getIntervalRange());
		dest.setIntervalStart( src.getIntervalStart());
		dest.setSortDirection( src.getSortDirection());
		dest.setFilters( src.getFilters());
		dest.setSorts( src.getSorts() );
		dest.setIsComplexExpression( isComplexExpression );
		return dest;
	}
	/**
	 * @param groupSpecs
	 * @param i
	 */
	static int getTempComputedColumnType( int i )
	{
		int interval = i;
		if( interval == IQuery.GroupSpec.DAY_INTERVAL 
			|| interval == IQuery.GroupSpec.HOUR_INTERVAL
			|| interval == IQuery.GroupSpec.MINUTE_INTERVAL
			|| interval == IQuery.GroupSpec.SECOND_INTERVAL
			|| interval == IQuery.GroupSpec.MONTH_INTERVAL
			|| interval == IQuery.GroupSpec.QUARTER_INTERVAL
			|| interval == IQuery.GroupSpec.YEAR_INTERVAL
			|| interval == IQuery.GroupSpec.WEEK_INTERVAL )
			interval = DataType.DATE_TYPE;
		else if ( interval == IQuery.GroupSpec.NUMERIC_INTERVAL )
			interval = DataType.DOUBLE_TYPE;
		else if ( interval == IQuery.GroupSpec.STRING_PREFIX_INTERVAL )
			interval = DataType.STRING_TYPE;