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
{
					delAllBtn.setEnabled( false );
				}
			}
		} );
		addExpressionValue.addModifyListener( new ModifyListener( ) {
			public void modifyText( ModifyEvent e )
			{
				checkAddButtonStatus( );
				updateButtons( );
			}
		} );
		addExpressionValue.addListener( SWT.Verify, expValueVerifyListener );
		addExpressionValue.addListener( SWT.Selection, popBtnSelectionListener );
		addExpressionValue.setItems( popupItems );
		parent.getParent( ).layout( true, true );
		
		return 1;
	}
	
	protected void checkEditDelButtonStatus( )
	{
		if ( tableViewer == null )
		{
			return;
		}
		boolean enabled = ( tableViewer.getSelection( ) == null ) ? false
				: true;
		if ( enabled == true
				&& tableViewer.getSelection( ) instanceof StructuredSelection )