Bug 161222 Decoration label should be optional in Gantt Chart
It should not be mandatory to specify a decoration label for Gantt Charts, this can be left blank. Currently the UI and Engine enforce a data definition to be specified for it.
chart/org.eclipse.birt.chart.engine/src/org/eclipse/birt/chart/internal/datafeed/ResultSetDataSet.java
* Creates the resultset using a given list.
	 * 
	 * @param lst
	 */
	public ResultSetDataSet( List lst, int dataType )
	{
		this.rsw = null;
		this.iColumnCount = 1;
		this.iaColumnIndexes = new int[]{
			0
		};
		this.lStartRow = 0;
		this.lEndRow = lst.size( );
		this.oaTuple = new Object[iColumnCount];
		this.listMode = true;
		this.listDataType = dataType;
		it = lst.iterator( );
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.birt.chart.datafeed.IResultSetDataSet#hasNext()
	 */
	public boolean hasNext( )
	{
		return ( lRow < lEndRow );
	}
	/*
	 * (non-Javadoc)
	 *