Bug 132515 Expression like "Toltal.rank(Tolta.ave(row[a]),ture,Null,1)" is return an error
Description: Add an expression like "Toltal.rank(Tolta.ave(row[a]),ture,Null,1)" is return an error.The nesting "Toltal" seem not to be work. Step to reproduce: 1.new a datasource and dataset 2.drag the dataset to layout veiw for a table 3.set a group on the table 4.Insert a data into the group header with the expression e.g. "Toltal.rank(Tolta.ave(row[a]),ture,Null,1)" Actual result: An error was thrown out Expected result: It should work correctly in order to support some requirments
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/impl/QueryExecutor.java
* 
	 * @throws DataException
	 */
	protected void openDataSource( ) throws DataException
	{
		assert odiDataSource == null;
		
		
		if ( dataSource != null )
		{
			
			if ( !dataSource.isOpen( )
					|| DataSetCacheManager.getInstance( ).doesLoadFromCache( ) == true )
			{
				
				
				
				dataSource.beforeOpen( );
				
				odiDataSource = createOdiDataSource( );
				 
				
				odiDataSource.setAppContext( queryAppContext );
				
				dataSource.openOdiDataSource( odiDataSource );
				dataSource.afterOpen( );
			}
			else
			{