Bug 123726 "Top n", "Bottom n" in highlight dialog doesn't work.
Description: "Top n", "Bottom n" in highlight dialog doesn't work. Steps to reproduce: 1. Add a highlight for a table. 2. Set highlight rule: "account_id", "top n", "3", let its font color red. 3. Preview the report, it doesn't work. Attached is design file.
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/impl/PreparedQuery.java
* @return the group count defined in report query
	 */
	int getGroupCount()
	{
		assert queryDefn != null;
		return queryDefn.getGroups().size();
	}
	
	/**
	 * PreparedQuery.Executor: executes a prepared query and maintains execute-time data and result
	 * set associated with an execution.
	 * 
	 * A PreparedQuery can be executed multiple times. Each execute is performed by one instance of 
	 * the Executor.
	 * 
	 * Each subclass of PreparedQuery is expected to have its own subclass of the Executor.
	 */
	abstract class Executor
	{
		protected 	IQuery			odiQuery;
		protected 	IDataSource		odiDataSource;
		protected 	DataSourceRuntime	dataSource;
		
		
		protected	DataSetRuntime	dataSet;
		
		
		protected	QueryResults	outerResults;
		
		protected 	AggregateCalculator		aggregates;