Add support for watch events and error notifications

pkg/analysis_server/test/src/plugin/notification_manager_test.dart

 // Copyright (c) 2017, 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 'package:analysis_server/plugin/protocol/protocol.dart' as server;
 import 'package:analysis_server/src/channel/channel.dart';
 import 'package:analysis_server/src/plugin/notification_manager.dart';
 import 'package:analyzer/file_system/memory_file_system.dart';
 import 'package:analyzer_plugin/protocol/protocol.dart' as plugin;
 import 'package:analyzer_plugin/protocol/protocol_constants.dart' as plugin;
@@ skipping 107 matching lines @@
     });
     plugin.Outline pluginOutline1 = pluginOutline(0, 0);
     plugin.AnalysisOutlineParams params =
         new plugin.AnalysisOutlineParams(fileA, [pluginOutline1]);
     manager.handlePluginNotification('a', params.toNotification());
 
     server.Outline serverOutline1 = serverOutline(0, 0);
     _verifyOutlines(fileA, serverOutline1);
   }
 
+  void test_handlePluginNotification_pluginError() {
+    bool isFatal = false;
+    String message = 'message';
+    String stackTrace = 'stackTrace';
+    plugin.PluginErrorParams params =
+        new plugin.PluginErrorParams(isFatal, message, stackTrace);
+    manager.handlePluginNotification('a', params.toNotification());
+    _verifyPluginError(isFatal, message, stackTrace);
+  }
+
   void test_recordAnalysisErrors_noSubscription() {
     server.AnalysisError error = serverAnalysisError(0, 0, file: fileA);
     manager.recordAnalysisErrors('a', fileA, [error]);
     expect(channel.sentNotification, isNull);
   }
 
   void test_recordAnalysisErrors_withSubscription() {
     manager.setAnalysisRoots([testDir], []);
     //
     // Errors should be reported when they are recorded.
@@ skipping 327 matching lines @@
     server.Notification notification = channel.sentNotification;
     expect(notification, isNotNull);
     expect(notification.event, 'analysis.outline');
     server.AnalysisOutlineParams params =
         new server.AnalysisOutlineParams.fromNotification(notification);
     expect(params, isNotNull);
     expect(params.file, fileName);
     expect(params.outline, equals(expectedOutline));
     channel.sentNotification = null;
   }
+
+  void _verifyPluginError(bool isFatal, String message, String stackTrace) {
+    server.Notification notification = channel.sentNotification;
+    expect(notification, isNotNull);
+    expect(notification.event, 'server.error');
+    server.ServerErrorParams params =
+        new server.ServerErrorParams.fromNotification(notification);
+    expect(params, isNotNull);
+    expect(params.isFatal, isFatal);
+    expect(params.message, message);
+    expect(params.stackTrace, stackTrace);
+    channel.sentNotification = null;
+  }
 }
 
 class TestChannel implements ServerCommunicationChannel {
   server.Notification sentNotification;
 
   @override
   void close() {
     fail('Unexpected invocation of close');
   }
 
   @override
   void listen(void onRequest(server.Request request),
       {Function onError, void onDone()}) {
     fail('Unexpected invocation of listen');
   }
 
   @override
   void sendNotification(server.Notification notification) {
     sentNotification = notification;
   }
 
   @override
   void sendResponse(server.Response response) {
     fail('Unexpected invocation of sendResponse');
   }
 }