aspnetcore: ActionContext.RouteData.Routers empty causes ArgumentOutOfRangeException in UrlHelper (Regression from 2.1)

Describe the bug

1. ActionContext.RouteData.Routers is empty collection with CompabilityVersion.Version_2_2
2. UrlHelper uses direct access to zero-element, instead calling .First() or .FirstOrDefault() with emergency return of ie. NullRouter protected IRouter Router => ActionContext.RouteData.Routers[0];
3. This causes ArgumentOutOfRangeException while using UrlHelper

To Reproduce

Steps to reproduce the behavior:

1. Using this version of ASP.NET Core ‘2.2’
2. Run this code:

Generate new WebApi project In Startup.cs

public void ConfigureServices(IServiceCollection services)
{
	services.AddRouting(opt => opt.LowercaseUrls = true);

	
	services.AddSingleton<IActionContextAccessor, ActionContextAccessor>();
	services.AddScoped<IUrlHelper>(implementationFactory =>
	{
		var actionContext = implementationFactory.GetService<IActionContextAccessor>().ActionContext;
		return new UrlHelper(actionContext);
	});

	services.AddMvc()
		.SetCompatibilityVersion(CompatibilityVersion.Version_2_2);
}

TestController.cs

using Microsoft.AspNetCore.Mvc;

[Route("api/test")]
public class TestController : Controller
{

    protected IUrlHelper UrlHelper {get;set;}

	public TestController(IUrlHelper urlHelper)
	{
        UrlHelper = urlHelper;
	}

	[HttpGet]
	public IActionResult ListAsync() 
	{
		var res = UrlHelper.Action(nameof(ListAsync));
		return Ok(res);
	}
}

1. Execute action GET /api/test
2. See error:

ArgumentOutOfRangeException: Index was out of range. Must be non-negative and less than the size of the collection.
 Parameter name: index
System.Collections.Generic.List<T>.get_Item(int index)
Microsoft.AspNetCore.Mvc.Routing.UrlHelper.get_Router()
Microsoft.AspNetCore.Mvc.Routing.UrlHelper.GetVirtualPathData(string routeName, RouteValueDictionary values)
Microsoft.AspNetCore.Mvc.Routing.UrlHelper.Action(UrlActionContext actionContext)
Microsoft.AspNetCore.Mvc.UrlHelperExtensions.Action(IUrlHelper helper, string action, string controller, object values, string protocol, string host, string fragment)
Microsoft.AspNetCore.Mvc.UrlHelperExtensions.Action(IUrlHelper helper, string action)
TestController.ListAsync() in TestController.cs
		var res = UrlHelper.Action(nameof(ListAsync));

1. Switch CompabilityVersion to CompatibilityVersion.Version_2_1
2. Watch action run as expected

Expected behavior

Action should return /api/test No ArgumentOutOfRangeException should be thrown

Additional context