Update ASP.NET Core 3.1-to-5.0 migration guide for RC2 (#20217)

Author: scottaddie

aspnetcore/migration/31-to-50.md

@@ -4,7 +4,7 @@ author: scottaddie
 description: Learn how to migrate an ASP.NET Core 3.1 project to ASP.NET Core 5.0.
 ms.author: scaddie
 ms.custom: mvc
-ms.date: 09/14/2020
+ms.date: 10/16/2020
 no-loc: ["ASP.NET Core Identity", cookie, Cookie, Blazor, "Blazor Server", "Blazor WebAssembly", "Identity", "Let's Encrypt", Razor, SignalR]
 uid: migration/31-to-50
 ---
@@ -41,7 +41,7 @@ If you rely upon a [global.json](/dotnet/core/tools/global-json) file to target
 {
   "sdk": {
 -    "version": "3.1.200"
-+    "version": "5.0.100-rc.1.20452.10"
++    "version": "5.0.100-rc.2.20479.15"
   }
 }
 ```
@@ -100,9 +100,9 @@ In the project file, update each [Microsoft.AspNetCore.*](https://www.nuget.org/
 -    <PackageReference Include="Microsoft.AspNetCore.JsonPatch" Version="3.1.6" />
 -    <PackageReference Include="Microsoft.Extensions.Caching.Abstractions" Version="3.1.6" />
 -    <PackageReference Include="System.Net.Http.Json" Version="3.2.1" />
-+    <PackageReference Include="Microsoft.AspNetCore.JsonPatch" Version="5.0.0-rc.1.*" />
-+    <PackageReference Include="Microsoft.Extensions.Caching.Abstractions" Version="5.0.0-rc.1.*" />
-+    <PackageReference Include="System.Net.Http.Json" Version="5.0.0-rc.1.*" />
++    <PackageReference Include="Microsoft.AspNetCore.JsonPatch" Version="5.0.0-rc.2.*" />
++    <PackageReference Include="Microsoft.Extensions.Caching.Abstractions" Version="5.0.0-rc.2.*" />
++    <PackageReference Include="System.Net.Http.Json" Version="5.0.0-rc.2.*" />
 </ItemGroup>
 ```
 
@@ -117,27 +117,35 @@ For apps using Docker, update your *Dockerfile* `FROM` statements and scripts. U
 
 As part of the move to ".NET" as the product name, the Docker images moved from the `mcr.microsoft.com/dotnet/core` repositories to `mcr.microsoft.com/dotnet`. For more information, see [dotnet/dotnet-docker#1939](https://github.com/dotnet/dotnet-docker/issues/1939).
 
-## Review breaking changes
-
-For breaking changes from .NET Core 3.1 to .NET 5.0, see [Breaking changes for migration from version 3.1 to 5.0](/dotnet/core/compatibility/3.1-5.0). ASP.NET Core and Entity Framework Core are also included in the list.
-
-## Changes to model binding in ASP.NET Core MVC and Razor Pages
+## Model binding changes in ASP.NET Core MVC and Razor Pages
 
 ### DateTime values are model bound as UTC times
 
-In ASP.NET Core 3.1 and earlier, `DateTime` values were model bound as local time where the timezone was determined by the server. `DateTime` values bound from input formatting (JSON) and `DateTimeOffset` values were bound as UTC timezones. In ASP.NET Core 5.0 and later, model binding consistently binds `DateTime` values with the UTC timezone.
+In ASP.NET Core 3.1 and earlier, `DateTime` values were model-bound as local time, where the timezone was determined by the server. `DateTime` values bound from input formatting (JSON) and `DateTimeOffset` values were bound as UTC timezones.
+
+In ASP.NET Core 5.0 and later, model binding consistently binds `DateTime` values with the UTC timezone.
 
-To retain the previous behavior, remove the `DateTimeModelBinderProvider` as part of the application startup:
+To retain the previous behavior, remove the `DateTimeModelBinderProvider` in `Startup.ConfigureServices`:
 
 ```csharp
-services.AddControllersWithViews(options => options.ModelBinderProviders.RemoveType<DateTimeModelBinderProvider>());
+services.AddControllersWithViews(options => 
+    options.ModelBinderProviders.RemoveType<DateTimeModelBinderProvider>());
 ```
 
-### ComplexObjectModelBinderProvider \ ComplexObjectModelBinder replace ComplexTypeModelBinderProvider \ ComplexTypeModelBinder 
+### ComplexObjectModelBinderProvider \ ComplexObjectModelBinder replace ComplexTypeModelBinderProvider \ ComplexTypeModelBinder
+
+To add support for model binding [C# 9 record types](/dotnet/csharp/whats-new/csharp-9#record-types), the <xref:Microsoft.AspNetCore.Mvc.ModelBinding.Binders.ComplexTypeModelBinderProvider> is:
 
-As part of adding support for model binding record types, the `ComplexTypeModelBinderProvider` is annotated as obsolete and is no longer registered by default. Applications that previously relied on the presence of the `ComplexTypeModelBinderProvider` in the `ModelBinderProviders` collection need to be updated to reference the new binder provider:
+* Annotated as obsolete.
+* No longer registered by default.
+
+Apps that rely on the presence of the `ComplexTypeModelBinderProvider` in the `ModelBinderProviders` collection need to reference the new binder provider:
 
 ```diff
 - var complexModelBinderProvider = options.ModelBinderProviders.OfType<ComplexTypeModelBinderProvider>();
 + var complexModelBinderProvider = options.ModelBinderProviders.OfType<ComplexObjectModelBinderProvider>();
 ```
+
+## Review breaking changes
+
+For breaking changes from .NET Core 3.1 to .NET 5.0, see [Breaking changes for migration from version 3.1 to 5.0](/dotnet/core/compatibility/3.1-5.0). ASP.NET Core and Entity Framework Core are also included in the list.