Bug 136833 Group key is affected by Generate All button in group.
Description: Group key is affected by Generate All button in group. Steps to reproduce: 1. Insert a list 2. Add a group, select a group key, then click Generate All button. Actual result: Group key disappeared, you have to reset it.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/GroupDialog.java
Composite tocArea = new Composite( composite, SWT.NONE );
		tocArea.setLayoutData( new GridData( GridData.FILL_HORIZONTAL ) );
		tocArea.setLayout( UIUtil.createGridLayoutWithoutMargin( 2, false ) );
		
		tocEditor = new Text( tocArea, SWT.SINGLE | SWT.BORDER );
		tocEditor.setLayoutData( new GridData( GridData.FILL_HORIZONTAL ) );
		Button exprButton = new Button( tocArea, SWT.PUSH );
		exprButton.setText( "..." ); 
		exprButton.addSelectionListener( new SelectionAdapter( ) {
			public void widgetSelected( SelectionEvent event )
			{
				ExpressionBuilder expressionBuilder = new ExpressionBuilder( tocEditor.getText( ) );
				expressionBuilder.setExpressionProvier( new ExpressionProvider( inputGroup ) );
				if ( expressionBuilder.open( ) == OK )
				{
					tocEditor.setText( expressionBuilder.getResult( ) );
				}
			}
		} );
	}
	/**
	 * Creates the title area
	 * 
	 * @param parent
	 *            the parent composite
	 */
	private void createTitleArea( Composite parent )
	{
		int margins = 2;