A second Rating Stars component will deselect the first when using Safari 601.1

[jessesesame]

When there are multiple rating star components on the page, input on a second component will undo input on the first. We have tested various devices and versions and found that it fails on Safari 601.1.

Steps to reproduce:

• Load test page included below with a Safari 601.1 mobile device.
• Touch the first component to input a value.
• Touch the second component to input a value.
• At this point the value entered for the first component is reset.

Versions used to reproduce the issue:

• Vaadin Version: 7.7.7
• Rating Stars Version: 2.1
• Safari 601.1 running on IOS 9.3.2

Test page used to reproduce the issue:

package ratingstars;
import com.vaadin.annotations.Theme;
import com.vaadin.annotations.VaadinServletConfiguration;
import com.vaadin.server.VaadinRequest;
import com.vaadin.server.VaadinServlet;
import com.vaadin.ui.UI;
import com.vaadin.ui.VerticalLayout;
import org.vaadin.teemu.ratingstars.RatingStars;
import javax.servlet.annotation.WebServlet;

@Theme("mytheme")
public class RatingStarsUi extends UI {

    @Override
    protected void init(VaadinRequest vaadinRequest) {
        final VerticalLayout layout = new VerticalLayout();
        layout.addComponent(new RatingStars());
        layout.addComponent(new RatingStars());
        layout.setMargin(true);
        layout.setSpacing(true);       
        setContent(layout);
    }

    @WebServlet(urlPatterns = "/*", name = "MyUIServlet", asyncSupported = true)
    @VaadinServletConfiguration(ui = RatingStarsUi.class, productionMode = false)
    public static class MyUIServlet extends VaadinServlet {
    }
}

This behavior is not reproducible from a more recent version Safari 602.1 (IOS 10.2.1).