Initial support for getting fixes from plugins

pkg/analysis_server/test/src/plugin/plugin_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 'dart:async';
 import 'dart:io' as io;
 
 import 'package:analysis_server/src/plugin/notification_manager.dart';
 import 'package:analysis_server/src/plugin/plugin_manager.dart';
 import 'package:analyzer/context/context_root.dart';
@@ skipping 122 matching lines @@
     await withPlugin(
         pluginName: 'plugin1',
         test: (String plugin1Path) async {
           await withPlugin(
               pluginName: 'plugin2',
               test: (String plugin2Path) async {
                 ContextRoot contextRoot = new ContextRoot(pkgPath, []);
                 await manager.addPluginToContextRoot(contextRoot, plugin1Path);
                 await manager.addPluginToContextRoot(contextRoot, plugin2Path);
 
-                List<Future<Response>> responses = manager.broadcast(
+                Map<PluginInfo, Future<Response>> responses = manager.broadcast(
                     contextRoot,
                     new CompletionGetSuggestionsParams(
                         '/pkg1/lib/pkg1.dart', 100));
                 expect(responses, hasLength(2));
 
                 await manager.stopAll();
               });
         });
     pkg1Dir.deleteSync(recursive: true);
   }
@@ skipping 65 matching lines @@
   void setUp() {
     resourceProvider = new MemoryResourceProvider();
     byteStorePath = '/byteStore';
     notificationManager = new TestNotificationManager();
     manager = new PluginManager(resourceProvider, byteStorePath,
         notificationManager, InstrumentationService.NULL_SERVICE);
   }
 
   void test_broadcast_none() {
     ContextRoot contextRoot = new ContextRoot('/pkg1', []);
-    List<Future<Response>> responses = manager.broadcast(contextRoot,
+    Map<PluginInfo, Future<Response>> responses = manager.broadcast(contextRoot,
         new CompletionGetSuggestionsParams('/pkg1/lib/pkg1.dart', 100));
     expect(responses, hasLength(0));
   }
 
   void test_creation() {
     expect(manager.resourceProvider, resourceProvider);
     expect(manager.byteStorePath, byteStorePath);
     expect(manager.notificationManager, notificationManager);
   }
 
@@ skipping 307 matching lines @@
       void onNotification(Notification notification),
       {Function onError, void onDone()}) {
     fail('Unexpected invocation of listen');
   }
 
   @override
   void sendRequest(Request request) {
     sentRequests.add(request);
   }
 }