Update MAUI Exception Handling (#40765)

src/Components/README.md

@@ -26,6 +26,7 @@ The following contains a description of each sub-directory in the `Components` d
   - `Server`: Contains the implementation for WASM-specific extension methods and the launch logic for the debugging proxy
   - `WebAssembly`: Contains WebAssembly-specific implementations of the renderer, HostBuilder, etc.
   - `WebAssembly.Authentication`: Contains the WASM-specific implementations
+- `WebView`: Contains the source files to support [Blazor Hybrid](https://github.com/dotnet/maui/tree/main/src/BlazorWebView) within [`dotnet/maui`](https://github.com/dotnet/maui). Changes in this project can be tested with `dotnet/maui` following [this guide](https://github.com/dotnet/maui/wiki/Blazor-Desktop#aspnet-core).
 
 ## Development Setup
 

src/Components/WebView/WebView/src/IpcSender.cs

@@ -3,6 +3,7 @@
 
 using System;
 using System.Diagnostics.CodeAnalysis;
+using System.Runtime.ExceptionServices;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Components.RenderTree;
 using Microsoft.JSInterop;
@@ -62,8 +63,12 @@ public void SendByteArray(int id, byte[] data)
 
         public void NotifyUnhandledException(Exception exception)
         {
+            // Send the serialized exception to the WebView for display
             var message = IpcCommon.Serialize(IpcCommon.OutgoingMessageType.NotifyUnhandledException, exception.Message, exception.StackTrace);
             _dispatcher.InvokeAsync(() => _messageDispatcher(message));
+
+            // Also rethrow so the AppDomain's UnhandledException handler gets notified
+            _dispatcher.InvokeAsync(() => ExceptionDispatchInfo.Capture(exception).Throw());
         }
 
         private void DispatchMessageWithErrorHandling(string message)

src/Components/WebView/WebView/src/Services/WebViewRenderer.cs

@@ -1,7 +1,6 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
-using System.Runtime.ExceptionServices;
 using System.Text.Json;
 using Microsoft.AspNetCore.Components.RenderTree;
 using Microsoft.AspNetCore.Components.Web;
@@ -38,9 +37,6 @@ protected override void HandleException(Exception exception)
         {
             // Notify the JS code so it can show the in-app UI
             _ipcSender.NotifyUnhandledException(exception);
-
-            // Also rethrow so the AppDomain's UnhandledException handler gets notified
-            ExceptionDispatchInfo.Capture(exception).Throw();
         }
 
         protected override Task UpdateDisplayAsync(in RenderBatch renderBatch)