remove temporary fix

lib/src/_web_socket_connect/_web_socket_connect_html.dart

@@ -3,31 +3,6 @@ import 'dart:js_interop';
 
 import 'package:web/helpers.dart';
 
-// TODO(mytja): remove when https://github.com/dart-lang/web/commit/4cb5811ed06
-// is in a published release and the min constraint on pkg:web is updated
-/// [WebSocketEvents] is an extension to the main [WebSocket] class from
-/// package:web. It adds appropriate streams while https://github.com/dart-lang/web/commit/4cb5811ed06
-/// is not yet published.
-extension WebSocketEvents on WebSocket {
-  /// [onOpen] is a [Stream], which returns [Event]s upon
-  /// establishing new WebSocket connection.
-  Stream<Event> get onOpen => EventStreamProviders.openEvent.forTarget(this);
-
-  /// [onMessage] is a [Stream], which returns [MessageEvent]s upon
-  /// receiving messages through the WebSocket connection.
-  Stream<MessageEvent> get onMessage =>
-      EventStreamProviders.messageEvent.forTarget(this);
-
-  /// [onClose] is a [Stream], which returns [CloseEvent]s upon
-  /// WebSocket closure.
-  Stream<CloseEvent> get onClose =>
-      EventStreamProviders.closeEvent.forTarget(this);
-
-  /// [onError] is a [Stream], which returns [Event]s upon error.
-  Stream<Event> get onError =>
-      EventStreamProviders.errorEventSourceEvent.forTarget(this);
-}
-
 /// Create a WebSocket connection.
 Future<WebSocket> connect(
   String url, {