Add a WebSocketChannel class.

lib/src/web_socket/deprecated.dart

 // Copyright (c) 2014, 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.
 
 import 'dart:async';
 
 import 'package:crypto/crypto.dart';
 
-import 'copy/web_socket_impl.dart';
+import '../copy/web_socket_impl.dart';
+import 'channel.dart';
 
-/// An implementation of the WebSocket protocol that's not specific to "dart:io"
-/// or to any particular HTTP API.
-///
-/// Because this is HTTP-API-agnostic, it doesn't handle the initial [WebSocket
-/// handshake][]. This needs to be handled manually by the user of the code.
-/// Once that's been done, [new CompatibleWebSocket] can be called with the
-/// underlying socket and it will handle the remainder of the protocol.
-///
-/// [WebSocket handshake]: https://tools.ietf.org/html/rfc6455#section-4
+/// Use [WebSocketChannel] instead.
+@Deprecated("Will be removed in 3.0.0.")
 abstract class CompatibleWebSocket implements Stream, StreamSink {
   /// The interval for sending ping signals.
   ///
   /// If a ping message is not answered by a pong message from the peer, the
   /// `WebSocket` is assumed disconnected and the connection is closed with a
   /// [WebSocketStatus.GOING_AWAY] close code. When a ping signal is sent, the
   /// pong message must be received within [pingInterval].
   ///
   /// There are never two outstanding pings at any given time, and the next ping
   /// timer starts when the pong is received.
@@ skipping 62 matching lines @@
   /// Closes the web socket connection.
   ///
   /// [closeCode] and [closeReason] are the [close code][] and [reason][] sent
   /// to the remote peer, respectively. If they are omitted, the peer will see
   /// a "no status received" code with no reason.
   ///
   /// [close code]: https://tools.ietf.org/html/rfc6455#section-7.1.5
   /// [reason]: https://tools.ietf.org/html/rfc6455#section-7.1.6
   Future close([int closeCode, String closeReason]);
 }
-
-/// An exception thrown by [CompatibleWebSocket].
-class CompatibleWebSocketException implements Exception {
-  final String message;
-
-  CompatibleWebSocketException([this.message]);
-
-  String toString() => message == null
-      ? "CompatibleWebSocketException" :
-        "CompatibleWebSocketException: $message";
-}