Remove uses of the old plugin model from the analysis server

pkg/analysis_server/lib/src/status/diagnostics.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 'dart:async';
 import 'dart:convert';
 import 'dart:io';
 
 import 'package:analysis_server/protocol/protocol_generated.dart';
 import 'package:analysis_server/src/analysis_server.dart';
@@ skipping 1007 matching lines @@
     h3('Analyzer plugins');
     void writePlugin(Plugin plugin) {
       buf.write(plugin.uniqueIdentifier);
       buf.write(' (');
       buf.write(plugin.runtimeType);
       buf.write(')');
     }
 
     List<Plugin> plugins = [
       AnalysisEngine.instance.enginePlugin,
-      server.serverPlugin
     ];
     plugins.addAll(server.userDefinedPlugins);
     ul(plugins, writePlugin);
   }
 }
 
 class ProfilePage extends DiagnosticPageWithNav {
   ProfilePage(DiagnosticsSite site)
       : super(site, 'profile', 'Profiling Info',
             description: 'Profiling performance tag data.');
@@ skipping 160 matching lines @@
     h3('Execution domain');
     ul(ExecutionService.VALUES, (item) {
       if (domain.onFileAnalyzed != null) {
         buf.write('$item (has subscriptions)');
       } else {
         buf.write('$item (no subscriptions)');
       }
     });
   }
 }