Bug 129144 Support suppressDuplicates property on table row in report engine
See 129143 for detail. This only needs to be supported for data item in a detail row of a table.
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/ir/IReportItemVisitor.java
* 
	 * @param text
	 *            the text item to be visited
	 */
	Object visitTextItem(TextItemDesign text, Object value);
	/**
	 * visit label item
	 * 
	 * @param label
	 *            the label item to be visited
	 */
	Object visitLabelItem(LabelItemDesign label, Object value);
	/**
	 * visit data item
	 * 
	 * @param data
	 *            the data item to be visited
	 */
	Object visitDataItem(DataItemDesign data, Object value);
	/**
	 * visit multi-line data item
	 * 
	 * @param multiLine
	 *            the multi-line item to be visited.
	 */
	Object visitMultiLineItem(MultiLineItemDesign multiLine, Object value);
	/**
	 * visit grid item
	 * 
	 * @param grid