Bug 168808 Display text is lost after launching import values dialog
Steps to reproduce: 1.new a parameter; 2.select list box control type; 3.press "Import Values" button to import some values; 4.assign display texts for the imported values; 5.press "Import Values" button to launch import values dialog again; 6.press ok button on dialog; Expected result: The previous assigned display texts are remained. Actual result: The previous display texts are lost.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/ParameterDialog.java
Composite buttonBar = new Composite( tableAreaComposite, SWT.NONE );
		buttonBar.setLayout( UIUtil.createGridLayoutWithoutMargin( 4, false ) );
		buttonBar.setLayoutData( new GridData( GridData.FILL_HORIZONTAL ) );
		importValue = new Button( buttonBar, SWT.PUSH );
		importValue.setText( BUTTON_LABEL_IMPORT );
		setButtonLayoutData( importValue );
		
		importValue.setEnabled( !inputParameter.getModuleHandle( )
				.getVisibleDataSets( )
				.isEmpty( ) );
		importValue.addSelectionListener( new SelectionAdapter( ) {
			public void widgetSelected( SelectionEvent e )
			{
				boolean defaultValueRemoved = true;
				String type = getSelectedDataType( );
				List choices = new ArrayList( );
				for ( Iterator iter = choiceList.iterator( ); iter.hasNext( ); )
				{
					SelectionChoice choice = (SelectionChoice) iter.next( );
					choices.add( choice.getValue( ) );
				}
				ImportValueDialog dialog = new ImportValueDialog( type, choices );
				if ( dialog.open( ) == OK )
				{
					String[] importValues = (String[]) dialog.getResult( );
					choiceList.clear( );
					for ( int i = 0; i < importValues.length; i++ )
					{
						SelectionChoice choice = StructureFactory.createSelectionChoice( );
						choice.setValue( importValues[i] );