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/parser/EngineIRVisitor.java
if ( style.isEmpty( ) )
		{
			return null;
		}
		rule.setStyle( style );
		ConditionalExpression condExpr = new ConditionalExpression( rule
				.getTestExpression( ),
				toDteFilterOperator( rule.getOperator( ) ), rule.getValue1( ),
				rule.getValue2( ) );
		rule.setConditionExpr( condExpr );
		return rule;
	}
	/**
	 * create highlight defined in the handle.
	 * 
	 * @param item
	 *            styled item.
	 */
	protected void setHighlight( StyledElementDesign item, String defaultStr )
	{
		StyleHandle handle = item.getHandle( ).getPrivateStyle( );
		if ( handle == null )
		{
			return;
		}
		
		Iterator iter = handle.highlightRulesIterator( );
		if ( iter == null )
		{
			return;