Bug 122941 Group interval range resets to 1
1. Create a group based on orders.orderNumber. 2. Specify an interval range of 100. 3. Do not check "Use fixed base value for interval" 4. Preview the report. Report groups on every order number. 5. Open the group editor. The interval range is set to 1.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/GroupDialog.java
*            the parent composite
	 */
	private void createFieldArea( Composite parent )
	{
		Composite composite = new Composite( parent, SWT.NONE );
		composite.setLayout( new GridLayout( ) );
		GridData gd = new GridData( GridData.FILL_BOTH );
		gd.widthHint = 200;
		composite.setLayoutData( gd );
		
		new Label( composite, SWT.NONE ).setText( GROUP_DLG_GROUP_NAME_LABEL );
		
		nameEditor = new Text( composite, SWT.SINGLE | SWT.BORDER );
		nameEditor.setLayoutData( new GridData( GridData.FILL_HORIZONTAL ) );
		
		new Label( composite, SWT.NONE ).setText( GROUP_DLG_GROUP_KEY_LABEL );
		
		Composite keyArea = new Composite( composite, SWT.NONE );
		keyArea.setLayoutData( new GridData( GridData.FILL_HORIZONTAL ) );
		keyArea.setLayout( UIUtil.createGridLayoutWithoutMargin( 2, false ) );
		keyChooser = new Combo( keyArea, SWT.DROP_DOWN );
		keyChooser.setLayoutData( new GridData( GridData.FILL_HORIZONTAL ) );
		Button exprButton = new Button( keyArea, SWT.PUSH );
		exprButton.setText( "..." ); 
		exprButton.addSelectionListener( new SelectionAdapter( ) {
			public void widgetSelected( SelectionEvent event )
			{
				ExpressionBuilder expressionBuilder = new ExpressionBuilder( getKeyExpression( ) );
				expressionBuilder.setExpressionProvier( new ExpressionProvider( dataSetList ) );
				if ( expressionBuilder.open( ) == OK )