Bug 147263 Data can't be retrieved for extended item
Steps to reproduce: 1.Add a table in library 2.New a report, extend lib.table 3.Add a filter on table, choose "select value" Expected result: Available value will be listed Actual result: Error: The expression's value can not be retrieved. The DataSetHandle shouldn't be null.
data/org.eclipse.birt.report.data.adapter/src/org/eclipse/birt/report/data/adapter/impl/DataRequestSessionImpl.java
modelAdaptor = new ModelAdapter( context );
		sessionContext = context;
		
		
		
		
		
	}
	/*
	 * @see org.eclipse.birt.report.data.adaptor.impl.IDataRequestSession#defineDataSource(org.eclipse.birt.data.engine.api.IBaseDataSourceDesign)
	 */
	public void defineDataSource( IBaseDataSourceDesign design )
			throws BirtException
	{
		dataEngine.defineDataSource( design );
	}
	/*
	 * @see org.eclipse.birt.report.data.adaptor.impl.IDataRequestSession#defineDataSet(org.eclipse.birt.data.engine.api.IBaseDataSetDesign)
	 */
	public void defineDataSet( IBaseDataSetDesign design ) throws BirtException
	{
		dataEngine.defineDataSet( design );
	}
	/*
	 * @see org.eclipse.birt.report.data.adaptor.api.DataRequestSession#getDataSetMetaData(java.lang.String,
	 *      boolean)
	 */
	public IResultMetaData getDataSetMetaData( String dataSetName,
			boolean useCache ) throws BirtException
	{