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/ResultSetWrapper.java
}
	/**
	 * Returns the row count in specified group.
	 * 
	 * @param iGroupIndex
	 * @return
	 */
	public int getGroupRowCount( int iGroupIndex )
	{
		int startRow = ( iGroupIndex <= 0 ) ? 0
				: iaGroupBreaks[iGroupIndex - 1];
		int endRow = ( iGroupIndex > iaGroupBreaks.length - 1 ) ? getRowCount( )
				: iaGroupBreaks[iGroupIndex];
		return endRow - startRow;
	}
	/**
	 * Returns a pre-computed column count associated with the resultset wrapper
	 * instance
	 * 
	 * @return A pre-computed column count associated with the resultset wrapper
	 *         instance
	 */
	public int getColumnCount( )
	{
		return saExpressionKeys.length;
	}
	/**
	 * Returns the number of rows of data associated with the resultset wrapper
	 * instance
	 *