[web] Test harness fixes for Dart2Wasm.

lib/web_ui/dev/chrome.dart

@@ -82,10 +82,8 @@ class Chrome extends Browser {
       final String dir = environment.webUiDartToolDir.createTempSync('test_chrome_user_data_').resolveSymbolicLinksSync();
       final String jsFlags = enableWasmGC ? <String>[
         '--experimental-wasm-gc',
-        '--wasm-gc-js-interop',
         '--experimental-wasm-stack-switching',
         '--experimental-wasm-type-reflection',
-        '--wasm-gc-js-interop',
       ].join(' ') : '';
       final List<String> args = <String>[
         if (jsFlags.isNotEmpty) '--js-flags=$jsFlags',

lib/web_ui/pubspec.yaml

@@ -26,7 +26,7 @@ dev_dependencies:
   shelf_static: any
   shelf_web_socket: any
   stack_trace: any
-  stream_channel: any
+  stream_channel: 2.1.1
   test: 1.22.0
   test_api: any
   test_core: any

web_sdk/web_engine_tester/lib/static/host.dart

@@ -18,7 +18,10 @@ import 'package:ui/src/engine/dom.dart';
 
 /// A class defined in content shell, used to control its behavior.
 @JS()
-class _TestRunner {
+@staticInterop
+class _TestRunner {}
+
+extension _TestRunnerExtension on _TestRunner {
   external void waitUntilDone();
 }
 
@@ -32,15 +35,20 @@ external _TestRunner? get testRunner; // ignore: library_private_types_in_public
 /// debugging.
 @JS()
 @anonymous
+@staticInterop
 class _JSApi {
   external factory _JSApi({void Function() resume, void Function() restartCurrent});
+}
 
+extension _JSApiExtension on _JSApi {
   /// Causes the test runner to resume running, as though the user had clicked
   /// the "play" button.
+  // ignore: unused_element
   external Function get resume;
 
   /// Causes the test runner to restart the current test once it finishes
   /// running.
+  // ignore: unused_element
   external Function get restartCurrent;
 }
 

web_sdk/web_engine_tester/pubspec.yaml

@@ -6,7 +6,7 @@ environment:
 
 dependencies:
   js: 0.6.4
-  stream_channel: 2.1.0
+  stream_channel: 2.1.1
   test: 1.22.0
   webkit_inspection_protocol: 1.0.0
   stack_trace: 1.10.0