Bug 135790 ClassCastException in RowData.
ClassCastException is thrown in RowData line 81(IBaseExpression expr = ( IBaseExpression ) valueExpressions.get( index - 1 );).
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/executor/ListItemExecutor.java
{
	/**
	 * @param context
	 *            execution context
	 * @param visitor
	 *            visitor object for driving the execution
	 */
	protected ListItemExecutor( ExecutionContext context,
			IReportItemVisitor visitor )
	{
		super( context, visitor );
	}
	/**
	 * Execute a listint and create the contents.
	 * 
	 * List create a serials of contents.
	 * 
	 * The execution process is:
	 * 
	 * <li> create an container which will contain all the contents it creates.