jason feedback

lib/ui/ui_dart_state.cc

@@ -231,6 +231,9 @@ void UIDartState::HandlePlatformMessage(
         platform_message_handler_.lock();
     if (handler) {
       handler->HandlePlatformMessage(std::move(message));
+    } else {
+      FML_DLOG(WARNING) << "Dropping background isolate platform message on "
+                        << message->channel();
     }
   }
 }

lib/ui/window/platform_message_response_dart_port.cc

@@ -4,6 +4,7 @@
 
 #include "flutter/lib/ui/window/platform_message_response_dart_port.h"
 
+#include <array>
 #include <utility>
 
 #include "flutter/common/task_runners.h"
@@ -51,13 +52,14 @@ void PlatformMessageResponseDartPort::Complete(
   response_data.value.as_external_typed_data.peer = copy;
   response_data.value.as_external_typed_data.callback = FreeFinalizer;
 
-  Dart_CObject* response_values[2] = {&response_identifier, &response_data};
+  std::array<Dart_CObject*, 2> response_values = {&response_identifier,
+                                                  &response_data};
 
   Dart_CObject response = {
       .type = Dart_CObject_kArray,
   };
-  response.value.as_array.length = 2;
-  response.value.as_array.values = response_values;
+  response.value.as_array.length = response_values.size();
+  response.value.as_array.values = response_values.data();
 
   bool did_send = Dart_PostCObject(send_port_, &response);
   FML_CHECK(did_send);

lib/web_ui/lib/platform_dispatcher.dart

@@ -16,6 +16,14 @@ typedef PlatformMessageCallback = void Function(
 typedef PlatformConfigurationChangedCallback = void Function(PlatformConfiguration configuration);
 typedef ErrorCallback = bool Function(Object exception, StackTrace stackTrace);
 
+// ignore: avoid_classes_with_only_static_members
+/// A token that represents a root isolate.
+class RootIsolateToken {
+  static RootIsolateToken? get instance {
+    throw UnsupportedError('Root isolate not identifiable on web.');
+  }
+}
+
 abstract class PlatformDispatcher {
   static PlatformDispatcher get instance => engine.EnginePlatformDispatcher.instance;
 
@@ -55,9 +63,7 @@ abstract class PlatformDispatcher {
     int identifier,
     Object port);
 
-  int registerRootIsolate();
-
-  void registerBackgroundIsolate(int rootIsolateId);
+  void registerBackgroundIsolate(RootIsolateToken token);
 
   PlatformMessageCallback? get onPlatformMessage;
   set onPlatformMessage(PlatformMessageCallback? callback);

lib/web_ui/lib/src/engine/platform_dispatcher.dart

@@ -354,12 +354,7 @@ class EnginePlatformDispatcher extends ui.PlatformDispatcher {
   }
 
   @override
-  int registerRootIsolate() {
-    throw Exception("Isolates aren't supported in web.");
-  }
-
-  @override
-  void registerBackgroundIsolate(int rootIsolateId) {
+  void registerBackgroundIsolate(RootIsolateToken token) {
     throw Exception("Isolates aren't supported in web.");
   }
 

shell/common/shell.cc

@@ -593,8 +593,7 @@ void Shell::RunEngine(
       task_runners_.GetUITaskRunner(),
       fml::MakeCopyable(
           [run_configuration = std::move(run_configuration),
-           weak_engine = weak_engine_, result,
-           platform_message_handler = platform_message_handler_]() mutable {
+           weak_engine = weak_engine_, result]() mutable {
             if (!weak_engine) {
               FML_LOG(ERROR)
                   << "Could not launch engine with configuration - no engine.";