[dart2wasm] Compare named argument names by equality instead of identity

This fixes #60059 when `--minify` is not used.

With minification we expect that runtime and const symbols won't be
equal or identical, even when the symbol names are the same.

Issue: https://github.com/dart-lang/sdk/issues/60059
Change-Id: Id6560558e2bd00cd9bef1f0026e2bd92a74d82fc
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/414783
Reviewed-by: Martin Kustermann <kustermann@google.com>
Commit-Queue: Ömer Ağacan <omersa@google.com>

sdk/lib/_internal/wasm/lib/named_parameters.dart

@@ -5,15 +5,24 @@
 part of "core_patch.dart";
 
 /// Finds a named parameter in a named parameter list passed to a dynamic
-/// forwarder and returns the index of the value of that named parameter.
-/// Returns `null` if the name is not in the list.
+/// forwarder or `Function.apply` and returns the index of the value of that
+/// named parameter. Returns `null` if the name is not in the list.
 @pragma("wasm:entry-point")
 int? _getNamedParameterIndex(
   WasmArray<Object?> namedArguments,
   Symbol paramName,
 ) {
   for (int i = 0; i < namedArguments.length; i += 2) {
-    if (identical(namedArguments[i], paramName)) {
+    // `Symbol.==` does not check identity so we have a fast path here checking
+    // identities.
+    //
+    // We can't check just identities as the symbols in the list may not be
+    // constants in `Function.apply`.
+    //
+    // Also, `paramName` will always be a constant, so with `--minify` it can
+    // only be equal to a symbol in the list if it's also identical to it.
+    if (identical(namedArguments[i], paramName) ||
+        (!minify && unsafeCast<Symbol>(namedArguments[i]) == paramName)) {
       return i + 1;
     }
   }

tests/web/wasm/function_apply_minify_test.dart

@@ -0,0 +1,25 @@
+// 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.
+
+// dart2wasmOptions=--extra-compiler-option=--minify
+
+import 'package:expect/expect.dart';
+
+void f({int a = 0}) {
+  Expect.equals(123, a);
+}
+
+bool get runtimeTrue => int.parse('1') == 1;
+
+void main() {
+  // With minification, non-const symbols won't be identical or equal to the
+  // const symbols, so `Symbol('a')` here won't match `a` in the `f`'s named
+  // parameters and `Function.apply` will throw an error.
+  Expect.throws<NoSuchMethodError>(
+    () => Function.apply((runtimeTrue ? f : (() {})), [], {Symbol('a'): 123}),
+  );
+
+  // `const` symbols will work as before.
+  Function.apply((runtimeTrue ? f : (() {})), [], {#a: 123});
+}