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
VisibilityRuleDesign hide = createHide( (HideRuleHandle) visibilityRulesIterator
						.next( ) );
				visibility.addRule( hide );
			}
			if ( visibility.count( ) == 0 )
			{
				return null;
			}
			return visibility;
		}
		return null;
	}
	/**
	 * Creates the visibility rule( i.e. the hide)
	 * 
	 * @param handle
	 *            the DE's handle
	 * @return the created visibility rule
	 */
	protected VisibilityRuleDesign createHide( HideRuleHandle handle )
	{
		VisibilityRuleDesign rule = new VisibilityRuleDesign( );
		rule.setExpression( createExpression( handle.getExpression( ) ) );
		rule.setFormat( handle.getFormat( ) );
		return rule;
	}
	/**
	 * setup the attribute of report item
	 * 
	 * @param item