Add compiler-specific expectations for object_members_test

This test was intended to capture the existing state of
object members for JS interop and dart:html objects. At some
point, it started failing in ddc, so we add the correct
compiler-specific expectations instead to get it to pass.

Change-Id: I130efc9927a5cb74dafa1b5beb856c7a6ee5a9aa
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/425882
Reviewed-by: Nicholas Shahan <[email protected]>
Commit-Queue: Srujan Gaddam <[email protected]>

Author: srujzs

tests/web/internal/object_members_test.dart

@@ -13,7 +13,9 @@ import 'package:js/js.dart';
 import 'package:expect/legacy/minitest.dart'; // ignore: deprecated_member_use_from_same_package
 
 import 'dart:html';
-import 'dart:_interceptors' show JSObject;
+import 'dart:_interceptors' show JSObject, LegacyJavaScriptObject;
+
+const isDart2JS = const bool.fromEnvironment('dart.library._dart2js_only');
 
 @JS()
 external void eval(String code);
@@ -54,17 +56,27 @@ void main() {
   expect(noSuchMethodErrorThrown, isTrue);
   expect(div.runtimeType, DivElement);
 
-  // `toString` for `dart:html` types that do not have an overridden `toString`
-  // should look up the type through the proto.
-  expect(window.navigator.toString(), "Instance of 'Navigator'");
+  // `toString` for `dart:html` types depend on the implementation. dart2js
+  // provides a more readable string, whereas DDC just uses the underlying
+  // `toString`.
+  final navigatorToString = window.navigator.toString();
+  if (isDart2JS) {
+    expect(navigatorToString, "Instance of 'Navigator'");
+  } else {
+    expect(navigatorToString, "[object Navigator]");
+  }
 
   // Interop type.
   var js = JSClass();
   expect(js == js, true);
   expect(js == JSClass(), false);
-  // TODO(srujzs): Modify this once interop has random hash codes.
   hashCode = js.hashCode;
-  expect(hashCode, 0);
+  if (isDart2JS) {
+    // DDC adds a random hash code to the object (should use a weak map), but
+    // dart2js returns 0 for all `LegacyJavaScriptObject`s.
+    // TODO(srujzs): Modify this once interop has random hash codes.
+    expect(hashCode, 0);
+  }
   expect(hashCode, js.hashCode);
   expect(js.toString, isNotNull);
   // Should forward to underlying `toString` call.
@@ -76,5 +88,12 @@ void main() {
     noSuchMethodErrorThrown = false;
   } catch (_) {}
   expect(noSuchMethodErrorThrown, isTrue);
-  expect(js.runtimeType, JSObject);
+  final runtimeType = js.runtimeType;
+  if (isDart2JS) {
+    // dart2js explicitly returns `JSObject` as the `runtimeType` for all
+    // `LegacyJavaScriptObject`s.
+    expect(runtimeType, JSObject);
+  } else {
+    expect(runtimeType, LegacyJavaScriptObject);
+  }
 }