compile.. open firefox.. and click in the button reset..
will appears scroll in all fields.. but this layout only broken in ff..

Code:
	public void onModuleLoad() {

		final TextField<String> master = new TextField<String>();
		master.setAllowBlank(false);
		master.setMaxLength(100);
		master.setFieldLabel("master");

		final ListStore<BeanModel> unMedidaStore = new ListStore<BeanModel>();

		final ComboBox<BeanModel> comboBox = new ComboBox<BeanModel>();
		comboBox.setFieldLabel("combo");
		comboBox.setStore(unMedidaStore);
		comboBox.setAllowBlank(false);
		comboBox.setDisplayField("combo");

		final NumberField precisao = new NumberField();
		precisao.setAllowBlank(false);
		precisao.setMaxLength(9);
		precisao.setFieldLabel("field");

		final FormData formData = new FormData("100%");

		final LayoutContainer left = new LayoutContainer();
		left.setStyleAttribute("paddingRight", "17px");
		FormLayout layout = new FormLayout();
		layout.setLabelAlign(LabelAlign.TOP);
		left.setLayout(layout);
		left.add(comboBox, formData);

		final LayoutContainer right = new LayoutContainer();
		right.setStyleAttribute("paddingRight", "17px");
		layout = new FormLayout();
		layout.setLabelAlign(LabelAlign.TOP);
		right.setLayout(layout);
		right.add(precisao, formData);

		final LayoutContainer main = new LayoutContainer();
		main.setWidth(554);
		main.setLayout(new ColumnLayout());
		main.add(left, new ColumnData(.5));
		main.add(right, new ColumnData(.5));

		final FormPanel form = new FormPanel();
		form.setHeaderVisible(false);
		form.setBorders(false);
		form.setLabelAlign(LabelAlign.TOP);
		form.setButtonAlign(HorizontalAlignment.CENTER);
		form.setFieldWidth(537);
		form.setBodyBorder(false);
		form.add(master);
		form.add(main);

		final Button button1 = new Button("reset");
		button1.addSelectionListener(new SelectionListener<ButtonEvent>() {
			@Override
			public void componentSelected(final ButtonEvent ce) {
				form.reset();
			}
		});

		form.addButton(button1);

		final Window window = new Window();
		window.setSize(600, 365);
		window.setModal(true);
		window.setBlinkModal(true);
		window.setFrame(true);
		window.setPlain(true);
		window.setResizable(false);
		window.setHeading("window");
		window.setLayout(new RowLayout(Orientation.VERTICAL));

		final ContentPanel formPanel = new ContentPanel();
		formPanel.setHeaderVisible(false);
		formPanel.add(form);
		formPanel.setStyleAttribute("padding", "5px");

		window.add(formPanel, new RowData(1, 1));
		window.show();
	}