BeforeEnterEvent's rerouteTo doesn't update the URL

<vaadin.version>10.0.0.beta10</vaadin.version> Example app: MainView.java

@Route("")
public class MainView extends VerticalLayout implements BeforeEnterObserver {

    @Override
    public void beforeEnter(BeforeEnterEvent event) {
        event.rerouteTo("second");
    }
}

SecondView.java

@Route("second")
public class SecondView extends VerticalLayout {

    public SecondView() {
        add(new Label("hello"));
    }
}

After opening the app at localhost, I see the “hello” label, but the URL is still http://localhost:8080/. I’d expect it to be http://localhost:8080/second

[pleku]

Acceptance Criteria

• add forwardTo method with the suitable overloads like with rerouteTo and same semantics
  • the URL should be updated, but there should not be another History state entry in the browser -> it needs to use history.replaceState instead of pushState
• add mention of this to the documentation after https://github.com/vaadin/flow-and-components-documentation/blob/master/documentation/routing/tutorial-routing-lifecycle.asciidoc#reroute as its own subtopic
• in addition to basic unit tests, there needs to be integration tests for this, similarly to the reroute feature
  • https://github.com/vaadin/flow/blob/master/flow-tests/test-root-context/src/main/java/com/vaadin/flow/uitest/ui/RerouteView.java
  • https://github.com/vaadin/flow/blob/master/flow-tests/test-root-context/src/test/java/com/vaadin/flow/uitest/ui/RerouteIT.java

[pleku]

We also have an issue for postponing showing the wrong url #3619, but I don’t see why on reroute we would not show the changed url out of the box. @Legioth or @caalador do you recall any specific reason for this or it is just not added ? I think a simple replaceState with the new url should be done.