Bug 135462 [Smoke][regression]Group can not be created.
Description: Group can not be created. Steps to reproduce: 1. new a data source and data set 2. Insert a table, bind it to dataset. 3. Add a group for table Result: org.eclipse.jface.util.Assert$AssertionFailedException: null argument; at org.eclipse.jface.util.Assert.isNotNull(Assert.java:149) at org.eclipse.jface.util.Assert.isNotNull(Assert.java:125) at org.eclipse.birt.report.designer.ui.dialogs.GroupDialog.createDialogArea(GroupDialog.java:199) at org.eclipse.jface.dialogs.Dialog.createContents(Dialog.java:785) at org.eclipse.jface.window.Window.create(Window.java:420) at org.eclipse.jface.dialogs.Dialog.create(Dialog.java:1101) at org.eclipse.birt.report.designer.internal.ui.dialogs.BaseDialog.open(BaseDialog.java:135) at org.eclipse.birt.report.designer.internal.ui.util.UIUtil.addGroup(UIUtil.java:435) at org.eclipse.birt.report.designer.internal.ui.util.UIUtil.createGroup(UIUtil.java:396) at org.eclipse.birt.report.designer.internal.ui.editors.schematic.editparts.TableEditPart.insertGroup(TableEditPart.java:1377) at org.eclipse.birt.report.designer.internal.ui.editors.schematic.actions.InsertPositionGroupAction.run(InsertGroupActionFactory.java:174) at org.eclipse.jface.action.Action.runWithEvent(Action.java:492) at org.eclipse.jface.action.ActionContributionItem.handleWidgetSelection(ActionContributionItem.java:530) at org.eclipse.jface.action.ActionContributionItem.access$2(ActionContributionItem.java:480) at org.eclipse.jface.action.ActionContributionItem$5.handleEvent(ActionContributionItem.java:392) at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:66) at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:925) at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:3287) at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:2907) at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:1899) at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:1863) at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:417) at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:143) at org.eclipse.ui.internal.ide.IDEApplication.run(IDEApplication.java:106) at org.eclipse.core.internal.runtime.PlatformActivator$1.run(PlatformActivator.java:99) at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:92) at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:68) at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:374) at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:169) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at org.eclipse.core.launcher.Main.invokeFramework(Main.java:338) at org.eclipse.core.launcher.Main.basicRun(Main.java:282) at org.eclipse.core.launcher.Main.run(Main.java:977) at org.eclipse.core.launcher.Main.main(Main.java:952)
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/GroupDialog.java
private static final String TAB_FILTER = Messages.getString( "GroupDialog.Tab.Filter" ); 
	private static final String GROUP_DLG_INCLUDE_FOOTER_LABEL = Messages.getString( "GroupDialog.Label.IncludeFooter" ); 
	private static final String GROUP_DLG_INCLUDE_HEADER_LABEL = Messages.getString( "GroupDialog.Label.IncludeHeader" ); 
	private static final String GROUP_DLG_HEADER_FOOTER_LABEL = Messages.getString( "GroupDialog.Label.HeaderFooter" ); 
	public static final String GROUP_DLG_INTERVAL_BASE_LABEL = Messages.getString( "GroupDialog.Label.IntervalBase" ); 
	private static final String GROUP_DLG_AREA_MSG = Messages.getString( "GroupDialog.Dialog.GroupDetail" ); 
	public static final String GROUP_DLG_TITLE_NEW = Messages.getString( "GroupDialog.Title.New" ); 
	public static final String GROUP_DLG_TITLE_EDIT = Messages.getString( "GroupDialog.Title.Edit" ); 
	public static final String GROUP_DLG_HIDE_DETAIL = Messages.getString( "GroupDialog.buttion.HideDetail" );
	private List dataSetList = null, columnList;
	private GroupHandle inputGroup;
	/**
	 * The name editor
	 */
	private Text nameEditor;
	/**
	 * The group key and interval type combo box.
	 */
	private Combo keyChooser, intervalType;
	/**
	 * The spinner to choose interval range;
	 */
	private Spinner intervalRange;
	private FormPage filterPage, sortPage;
	/**
	 * The include check box and sorting direction radio box
	 */
	private Button includeHeader, includeFooter, ascending, descending;
	private Button intervalBaseButton;
	private Text intervalBaseText;