Add back previously removed tests

pkg/analysis_server/test/mocks.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.
 
 library mocks;
 
 import 'dart:async';
 import 'dart:io';
 
+import 'package:analysis_server/src/channel.dart';
+import 'package:analysis_server/src/protocol.dart';
+
 /**
  * A mock [WebSocket] for testing.
  */
 class MockSocket<T> implements WebSocket {
 
   StreamController controller = new StreamController();
   MockSocket twin;
   Stream stream;
 
   factory MockSocket.pair() {
@@ skipping 19 matching lines @@
 
   StreamSubscription<T> listen(void onData(T event),
                      { Function onError, void onDone(), bool cancelOnError}) =>
     stream.listen(onData, onError: onError, onDone: onDone,
         cancelOnError: cancelOnError);
 
   Stream<T> where(bool test(T)) => stream.where(test);
 
   noSuchMethod(Invocation invocation) => super.noSuchMethod(invocation);
 }
+
+/**
+ * A mock [ServerCommunicationChannel] channel that does nothing.
+ */
+class MockServerChannel implements ServerCommunicationChannel {
+  @override
+  void listen(void onRequest(Request request), {void onError(), void onDone()}) {
+  }
+
+  @override
+  void sendNotification(Notification notification) {
+  }
+
+  @override
+  void sendResponse(Response response) {
+  }
+}