Remove uses of the old plugin model from the analysis server

pkg/analysis_server/test/services/correction/assist_test.dart

Index: pkg/analysis_server/test/services/correction/assist_test.dart
diff --git a/pkg/analysis_server/test/services/correction/assist_test.dart b/pkg/analysis_server/test/services/correction/assist_test.dart
index 16364881c36e07ee29f915921ca05125f451f910..62a8d9338d03665ef8f4c313439a088a52a9f6a0 100644
--- a/pkg/analysis_server/test/services/correction/assist_test.dart
+++ b/pkg/analysis_server/test/services/correction/assist_test.dart
@@ -6,7 +6,6 @@ import 'dart:async';
 
 import 'package:analysis_server/plugin/edit/assist/assist_core.dart';
 import 'package:analysis_server/plugin/edit/assist/assist_dart.dart';
-import 'package:analysis_server/src/plugin/server_plugin.dart';
 import 'package:analysis_server/src/services/correction/assist.dart';
 import 'package:analysis_server/src/services/correction/assist_internal.dart';
 import 'package:analyzer/dart/ast/ast.dart';
@@ -40,7 +39,6 @@ class AssistProcessorTest extends AbstractSingleUnitTest {
   int offset;
   int length;
 
-  ServerPlugin plugin;
   Assist assist;
   SourceChange change;
   String resultCode;
@@ -111,11 +109,8 @@ class AssistProcessorTest extends AbstractSingleUnitTest {
   }
 
   void processRequiredPlugins() {
-    plugin = new ServerPlugin();
-
     List<Plugin> plugins = <Plugin>[];
     plugins.addAll(AnalysisEngine.instance.requiredPlugins);
-    plugins.add(plugin);
 
     ExtensionManager manager = new ExtensionManager();
     manager.processPlugins(plugins);