VirtualPathRoot is null in owin self-hosted environment

System.ArgumentNullException is raised when receiving batch requests due to VirtualPathRoot is null in owin self-hosted environment

Reproduce steps

Create a Owin Self-Hosted WebApi Application (Odata V4) and register ODataBatchHandler as in below code to handle Odata batch request.

public void Configuration(IAppBuilder app)
 {
   ...

   HttpConfiguration config = new HttpConfiguration()
   ODataBatchHandler batchHandler = new DefaultODataBatchHandler(GlobalConfiguration.DefaultServer);

   ...

   config.EnsureInitialized();

 }

Send a Batch request to Odata end point.

Expected result

Batch request should be prosessed.

Actual result

An Exception is occured.
Value cannot be null. Parameter name: virtualPathRoot ExceptionType : System.ArgumentNullException

Additional details

GlobalConfiguration.DefaultServer.Configuration.VirtualPathRoot is null in Self Hosted App but VirtualPathRoot has a value = "/" in ISS hosted environment.

Start by reproducing the Owin self-hosted Web API setup with DefaultODataBatchHandler and a batch request. Trace where GlobalConfiguration.DefaultServer.Configuration.VirtualPathRoot is consumed and compare the self-hosted and IIS-hosted values. Done means batch requests process without the virtualPathRoot ArgumentNullException in self-hosted mode.