DI API changes

Author: BrennanConroy

src/Microsoft.AspNet.Http.Extensions/UseMiddlewareExtensions.cs

@@ -22,8 +22,7 @@ public static IApplicationBuilder UseMiddleware(this IApplicationBuilder builder
             var applicationServices = builder.ApplicationServices;
             return builder.Use(next =>
             {
-                var typeActivator = applicationServices.GetRequiredService<ITypeActivator>();
-                var instance = typeActivator.CreateInstance(builder.ApplicationServices, middleware, new[] { next }.Concat(args).ToArray());
+                var instance = ActivatorUtilities.CreateInstance(builder.ApplicationServices, middleware, new[] { next }.Concat(args).ToArray());
                 var methodinfo = middleware.GetMethod("Invoke", BindingFlags.Instance | BindingFlags.Public);
                 var parameters = methodinfo.GetParameters();
                 if (parameters[0].ParameterType != typeof(HttpContext))

test/Microsoft.AspNet.Http.Extensions.Tests/UseWithServicesTests.cs

@@ -38,7 +38,6 @@ public async Task ServicesArePerRequest()
         {
             var services = new ServiceCollection()
                 .AddScoped<ITestService, TestService>()
-                .AddTransient<ITypeActivator, TypeActivator>()
                 .BuildServiceProvider();
             var builder = new ApplicationBuilder(services);
 
@@ -101,7 +100,6 @@ public async Task InvokeMethodWillAllowPerRequestServices()
         {
             var services = new ServiceCollection()
                 .AddScoped<ITestService, TestService>()
-                .AddTransient<ITypeActivator, TypeActivator>()
                 .BuildServiceProvider();
             var builder = new ApplicationBuilder(services);
             builder.UseMiddleware<TestMiddleware>();