Bug 136074 Filter editor needs to support column binding
In the Fitler tab of property editor for table/chart, Expression only shows dataset column, rather than column binding. Since column binding is supported for filter of table/chart, this is supposed to show the column binding.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/views/attributes/providers/SortingModelProvider.java
String saveValue = newValue;
		StructureHandle handle = (StructureHandle) element;
		if ( key.equals( SortKey.DIRECTION_MEMBER ) )
		{
			IChoice choice = choiceSet.findChoiceByDisplayName( newValue );
			if ( choice == null )
				saveValue = null;
			else
				saveValue = choice.getName( );
		}
		handle.getMember( key ).setStringValue( saveValue );
		return true;
	}
	/**
	 * Gets the choice set of one property
	 * 
	 * @param item