Bug 140705 Insert group does not work properly when cache preference is set
When cache preference is set, insert group does not work properly. Steps to reproduce problem: In Birt report designer: New a report design, data source, data set; Insert a table, drag several columns into table; Set cache preference for data set: check checkbox "Cache dataset data for report view"; Select "Cache and use first [] rows"; Enter '100' as row count. PREVIEW report; Insert group, Preview report again ---> problem happens: only header line will show up. All details are missing. Sample report is also attached.
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/executor/DataSourceAndDataSet.java
* @param resultHints2
	 * @return
	 */
	private boolean isEqualResultHints( List resultHints1, List resultHints2 )
	{
		if ( resultHints1 == resultHints2 )
			return true;
		int basicCol = isEqualBasicCol( resultHints1, resultHints2 );
		if ( basicCol == B_TRUE )
			return true;
		else if ( basicCol == B_FALSE )
			return false;
		Iterator it = resultHints1.iterator( );
		Iterator it2 = resultHints2.iterator( );
		while ( it.hasNext( ) )
		{
			IColumnDefinition cd = (IColumnDefinition) it.next( );
			IColumnDefinition cd2 = (IColumnDefinition) it2.next( );
			if ( isEqualColumnDefn( cd, cd2 ) == false )
				return false;
		}
		return true;
	}
	/**
	 * @param cd
	 * @param cd2
	 * @return
	 */
	private boolean isEqualColumnDefn( IColumnDefinition cd,
			IColumnDefinition cd2 )