[dart2wasm] Skip constructor entrypoints of dynamic callable anonymous mixins constructors.

These mixin constructors are now marked callable by the dynamic interface annotator: https://dart-review.googlesource.com/c/sdk/+/430002

However, they are not directly invokeable and trying to compile the constructor entrypoints causes dart2wasm to crash. So we explicitly skip them when considering dynamic callable constructors.

Note: This is blocking internal rolls as code patterns like this show up in our internal codebase.

Change-Id: I76383aec07bc53a0dbd1581c0577cba370d956f9
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/430801
Reviewed-by: Martin Kustermann <kustermann@google.com>
Commit-Queue: Nate Biggs <natebiggs@google.com>
Auto-Submit: Nate Biggs <natebiggs@google.com>

pkg/dart2wasm/lib/dynamic_modules.dart

@@ -605,7 +605,9 @@ class DynamicModuleInfo {
         // These types do not have directly invokable constructors.
         translator.classInfo[member.enclosingClass]!.struct
             .isSubtypeOf(translator.objectInfo.struct)) {
-      passReference(member.reference);
+      if (!member.enclosingClass.isAnonymousMixin) {
+        passReference(member.reference);
+      }
       passReference(member.initializerReference);
       passReference(member.constructorBodyReference);
     }

pkg/dynamic_modules/test/data/const_mixin_class/dynamic_interface.yaml

@@ -0,0 +1,7 @@
+# Copyright (c) 2025, the Dart project authors.  Please see the AUTHORS file
+# for details. All rights reserved. Use of this source code is governed by a
+# BSD-style license that can be found in the LICENSE file.
+
+callable:
+  - library: 'shared/shared.dart'
+    class: 'Foo'

pkg/dynamic_modules/test/data/const_mixin_class/main.dart

@@ -0,0 +1,16 @@
+// Copyright (c) 2025, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import '../../common/testing.dart' as helper;
+import 'package:expect/expect.dart';
+
+import 'shared/shared.dart' show Foo;
+
+/// A dynamic module is allowed to extend a class in the dynamic interface and
+/// override its members.
+void main() async {
+  final o = (await helper.load('entry1.dart'));
+  Expect.equals(const Foo(), o);
+  helper.done();
+}

pkg/dynamic_modules/test/data/const_mixin_class/modules/entry1.dart

@@ -0,0 +1,8 @@
+// Copyright (c) 2025, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import '../shared/shared.dart';
+
+@pragma('dyn-module:entry-point')
+Object? dynamicModuleEntrypoint() => const Foo();

pkg/dynamic_modules/test/data/const_mixin_class/shared/shared.dart

@@ -0,0 +1,9 @@
+// Copyright (c) 2025, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+mixin Mixin {}
+
+class Foo with Mixin {
+  const Foo();
+}