Bug 182895 Support sort on Level attribute.
Currently in OLAP engine we only support sort on level key value. We should go ahead to support sort on level attribute value.
data/org.eclipse.birt.data.tests/test/org/eclipse/birt/data/engine/olap/api/CubeFeaturesTest.java
IBinding binding4 = new Binding( "edge2level1");
		
		binding4.setExpression( new ScriptExpression("dimension[\"dimension2\"][\"level21\"]") );
		cqd.addBinding( binding4 );
		
		IBinding binding5 = new Binding( "measure2" );
		binding5.setExpression( new ScriptExpression("measure[\"measure1\"]") );
		cqd.addBinding( binding5 );
		
		DataEngine engine = DataEngine.newDataEngine( DataEngineContext.newInstance( DataEngineContext.DIRECT_PRESENTATION,
				null,
				null,
				null ) );
		this.createCube( engine );
		IPreparedCubeQuery pcq = engine.prepare( cqd, null );
		ICubeQueryResults queryResults = pcq.execute( null );
		try
		{
			queryResults.getCubeCursor( );
			fail( "Should not arrive here" );
		}
		catch ( Exception e )
		{
		}
	}
	
	
	/**
	 * Test use all dimension levels.