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
import org.eclipse.birt.report.data.adapter.api.DataRequestSession;
import org.eclipse.birt.report.data.adapter.api.DataSessionContext;
import org.eclipse.birt.report.data.adapter.api.IModelAdapter;
import org.eclipse.birt.report.data.adapter.api.IModelAdapter.ExpressionLocation;
import org.eclipse.birt.report.data.adapter.api.timeFunction.IArgumentInfo;
import org.eclipse.birt.report.data.adapter.api.timeFunction.IArgumentInfo.Period_Type;
import org.eclipse.birt.report.data.adapter.api.timeFunction.ITimeFunction;
import org.eclipse.birt.report.data.adapter.api.timeFunction.TimeFunctionManager;
import org.eclipse.birt.report.designer.core.model.SessionHandleAdapter;
import org.eclipse.birt.report.designer.data.ui.util.DataUtil;
import org.eclipse.birt.report.designer.internal.ui.data.DataService;
import org.eclipse.birt.report.designer.internal.ui.data.function.layout.IArgumentLayout;
import org.eclipse.birt.report.designer.internal.ui.dialogs.AbstractBindingDialogHelper;
import org.eclipse.birt.report.designer.internal.ui.dialogs.ResourceEditDialog;
import org.eclipse.birt.report.designer.internal.ui.dialogs.expression.ExpressionButton;
import org.eclipse.birt.report.designer.internal.ui.swt.custom.CLabel;
import org.eclipse.birt.report.designer.internal.ui.swt.custom.MenuButton;
import org.eclipse.birt.report.designer.internal.ui.util.ExpressionButtonUtil;
import org.eclipse.birt.report.designer.internal.ui.util.UIUtil;
import org.eclipse.birt.report.designer.nls.Messages;
import org.eclipse.birt.report.designer.ui.ReportPlatformUIImages;
import org.eclipse.birt.report.designer.ui.dialogs.IExpressionProvider;
import org.eclipse.birt.report.designer.ui.util.ExceptionUtil;
import org.eclipse.birt.report.designer.ui.views.attributes.providers.ChoiceSetFactory;
import org.eclipse.birt.report.designer.util.ColorManager;
import org.eclipse.birt.report.designer.util.DEUtil;
import org.eclipse.birt.report.item.crosstab.core.ICrosstabConstants;
import org.eclipse.birt.report.item.crosstab.core.de.AggregationCellHandle;
import org.eclipse.birt.report.item.crosstab.core.de.CrosstabReportItemHandle;
import org.eclipse.birt.report.item.crosstab.core.de.CrosstabViewHandle;