Bug 390669 [Accessibility]Press 'Tab' doesn't focus on the next report item when adding relative period aggregation.
xtab/org.eclipse.birt.report.item.crosstab.ui/src/org/eclipse/birt/report/item/crosstab/internal/ui/dialogs/CrosstabBindingDialogHelper.java
dateText.setLayoutData( gd );
		if ( expressionProvider == null )
		{
			if ( isAggregate( ) )
				expressionProvider = new CrosstabAggregationExpressionProvider( this.bindingHolder,
						this.binding );
			else
				expressionProvider = new CrosstabBindingExpressionProvider( this.bindingHolder,
						this.binding );
		}
		button = ExpressionButtonUtil.createExpressionButton( dateSelecionContainer,
				dateText,
				expressionProvider,
				this.bindingHolder,
				changeExprTypeListener,
				true,
				SWT.PUSH );
		dateText.setData( ExpressionButtonUtil.EXPR_TYPE,
				ExpressionType.CONSTANT );
		button.refresh( );
		new Label( radioContainer, SWT.NONE );
		dateFormatLbl = new Label( radioContainer, SWT.NONE );
		dateFormatLbl.setText( getDateHintText( ) );
		dateFormatLbl.setForeground( ColorManager.getColor( 128, 128, 128 ) );
		dateFormatLbl.setLayoutData( new GridData( GridData.FILL_HORIZONTAL ) );
		recentButton = new Button( radioContainer, SWT.RADIO );
		recentButton.addSelectionListener( new SelectionAdapter( ) {
			public void widgetSelected( SelectionEvent event )
			{
				if ( isStatic )