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/FilterModelProvider.java
}
	/**
	 * Gets the choice set of one property
	 * 
	 * @param item
	 *            ReportItem object
	 * @param key
	 *            Property key
	 * @return Choice set
	 */
	public String[] getChoiceSet( Object item, String key )
	{
		if ( key.equals( FilterCondition.OPERATOR_MEMBER ) )
		{
			choiceSet = ChoiceSetFactory.getStructChoiceSet( FilterCondition.FILTER_COND_STRUCT,
					key );
			return ChoiceSetFactory.getDisplayNamefromChoiceSet( choiceSet );
		}
		if ( item instanceof GroupHandle )
		{
			item = ( (GroupHandle) item ).getContainer( );
		}
		if ( !( item instanceof ReportItemHandle ) )
			return EMPTY;
		return getDataSetColumns( (ReportItemHandle) item );
	}
	/**
	 * Gets all columns in a dataSet.
	 * 
	 * @param handle