Rename helper extensions to not collide with pkg:web unreleased

lib/html.dart

@@ -96,15 +96,15 @@ class HtmlWebSocketChannel extends StreamChannelMixin
       }
       // The socket API guarantees that only a single open event will be
       // emitted.
-      innerWebSocket.onOpen.first.then((_) {
+      innerWebSocket.onOpenX.first.then((_) {
         _readyCompleter.complete();
         _listen();
       });
     }
 
     // The socket API guarantees that only a single error event will be emitted,
     // and that once it is no open or message events will be emitted.
-    innerWebSocket.onError.first.then((_) {
+    innerWebSocket.onErrorX.first.then((_) {
       // Unfortunately, the underlying WebSocket API doesn't expose any
       // specific information about the error itself.
       final error = WebSocketChannelException('WebSocket connection failed.');
@@ -115,11 +115,11 @@ class HtmlWebSocketChannel extends StreamChannelMixin
       _controller.local.sink.close();
     });
 
-    innerWebSocket.onMessage.listen(_innerListen);
+    innerWebSocket.onMessageX.listen(_innerListen);
 
     // The socket API guarantees that only a single error event will be emitted,
     // and that once it is no other events will be emitted.
-    innerWebSocket.onClose.first.then((event) {
+    innerWebSocket.onCloseX.first.then((event) {
       _closeCode = event.code;
       _closeReason = event.reason;
       _controller.local.sink.close();

lib/src/web_helpers.dart

@@ -7,11 +7,11 @@ import 'package:web/helpers.dart';
 // TODO(kevmoo): remove when https://github.com/dart-lang/web/commit/4cb5811ed06
 // is in a published release and the min constraint on pkg:web is updated
 extension WebSocketEvents on WebSocket {
-  Stream<Event> get onOpen => EventStreamProviders.openEvent.forTarget(this);
-  Stream<MessageEvent> get onMessage =>
+  Stream<Event> get onOpenX => EventStreamProviders.openEvent.forTarget(this);
+  Stream<MessageEvent> get onMessageX =>
       EventStreamProviders.messageEvent.forTarget(this);
-  Stream<CloseEvent> get onClose =>
+  Stream<CloseEvent> get onCloseX =>
       EventStreamProviders.closeEvent.forTarget(this);
-  Stream<Event> get onError =>
+  Stream<Event> get onErrorX =>
       EventStreamProviders.errorEventSourceEvent.forTarget(this);
 }

test/html_test.dart

@@ -70,7 +70,7 @@ void main() {
 
   test('communicates using an existing open WebSocket', () async {
     final webSocket = WebSocket('ws://localhost:$port');
-    await webSocket.onOpen.first;
+    await webSocket.onOpenX.first;
 
     final channel = HtmlWebSocketChannel(webSocket);