Remove extra test file and update Router

Author: captainsafia

src/Components/Components/ref/Microsoft.AspNetCore.Components.netcoreapp.cs

@@ -556,7 +556,7 @@ public LocationChangedEventArgs(string location, bool isNavigationIntercepted) {
         public bool IsNavigationIntercepted { [System.Runtime.CompilerServices.CompilerGeneratedAttribute] get { throw null; } }
         public string Location { [System.Runtime.CompilerServices.CompilerGeneratedAttribute] get { throw null; } }
     }
-    public partial class NavigationContext
+    public sealed partial class NavigationContext
     {
         internal NavigationContext() { }
         public System.Threading.CancellationToken CancellationToken { [System.Runtime.CompilerServices.CompilerGeneratedAttribute] get { throw null; } }

src/Components/Components/src/Routing/Router.cs

@@ -206,13 +206,14 @@ private async Task RunOnNavigateAsync(string path)
             // Create a new cancellation token source for this instance
             _onNavigateCts = new CancellationTokenSource();
             var navigateContext = new NavigationContext(path, _onNavigateCts.Token);
-            var task = OnNavigateAsync.InvokeAsync(navigateContext);
 
             // Create a cancellation task based on the cancellation token
             // associated with the current running task.
             var cancellationTaskSource = new TaskCompletionSource();
-            navigateContext.CancellationToken.Register(() =>
-                cancellationTaskSource.SetResult());
+            navigateContext.CancellationToken.Register(state =>
+                ((TaskCompletionSource)state).SetResult(), cancellationTaskSource);
+
+            var task = OnNavigateAsync.InvokeAsync(navigateContext);
 
             // If the user provided a Navigating render fragment, then show it.
             if (Navigating != null && task.Status != TaskStatus.RanToCompletion)