Bug 209126 DataException throws out when set highlight condition in sub-report[0302]
Description: Set highlight condition in sub-report, when "select value..." in the highlight dialog, DataException throws out. Build version:2.3.0.v20071108-0800 Steps to reproduce: 1.Get the attached report design file, which contains a sub-report. 2.Select the inner table, and then go to "highlight" tab in the property editor view to set a highlight rule. When click "select value...", DataException throws out. Error: The expression's value can not be retrieved. An error happened in data type conversion. Can not convert the value of org.eclipse.birt.data.engine.script.DataExceptionMocker@79c17b to Integer type.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/HighlightRuleBuilder.java
protected DesignElementHandle designHandle;
	private boolean isBoldChanged, isItalicChanged, isUnderlineChanged,
			isLinethroughChanged;
	private static final String DEFAULT_CHOICE = Messages.getString( "HighlightRuleBuilderDialog.text.Default" ); 
	private static final String[] SYSTEM_FONT_LIST = DEUtil.getSystemFontNames( );
	protected static final String VALUE_OF_THIS_DATA_ITEM = Messages.getString( "HighlightRuleBuilderDialog.choice.ValueOfThisDataItem" ); 
	private Map styles = new HashMap( );
	private Label applyLocalFormat;
	/**
	 * Default constructor.
	 * 
	 * @param parentShell
	 *            Parent Shell
	 * @param title
	 *            Windows Title
	 */
	public HighlightRuleBuilder( Shell parentShell, String title,
			HighlightHandleProvider provider )
	{
		super( parentShell, title );
		this.provider = provider;
	}
	private String[] getDataSetColumns( )
	{
		if ( columnList.isEmpty( ) )
		{
			return EMPTY;
		}
		String[] values = new String[columnList.size( )];
		for ( int i = 0; i < columnList.size( ); i++ )