Bug 182680 Use feature of new Aggregation framework of Data Engine.
DataEngine will implement new aggregation framework in 2.2.0RC0. After the implementation is finished Engine should go ahead to use new column bindings in definition of map/highlight.
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/api/impl/GetParameterDefinitionTask.java
queryDefn.setAutoBinding( true );
				
				IPreparedQuery query = dteSession.prepare( queryDefn,
						getAppContext( ) );
				IQueryResults result = query.execute( executionContext
						.getSharedScope( ) );
				IResultIterator resultIter = result.getResultIterator( );
				dataCache.put( parameterGroup.getName( ), resultIter );
				return;
			}
			catch ( BirtException ex )
			{
				ex.printStackTrace( );
			}
		}
		dataCache.put( parameterGroup.getName( ), null );
	}
	/**
	 * The second step to work with the cascading parameters. Get the selection
	 * choices for a parameter in the cascading group. The parameter to work on
	 * is the parameter on the next level in the parameter cascading hierarchy.
	 * For the "parameter to work on", please see the following example. Assume
	 * we have a cascading parameter group as Country - State - City. If user
	 * specified an empty array in groupKeyValues (meaning user doesn't have any
	 * parameter value), the parameter to work on will be the first level which
	 * is Country in this case. If user specified groupKeyValues as
	 * Object[]{"USA"} (meaning user has set the value of the top level), the
	 * parameter to work on will be the second level which is State in "USA" in
	 * this case. If user specified groupKeyValues as Object[]{"USA", "CA"}
	 * (meaning user has set the values of the top and the second level), the