Capture the request time for performance data and support forced shutdown

pkg/analyzer_plugin/lib/src/channel/isolate_channel.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:isolate';
 
 import 'package:analyzer/instrumentation/instrumentation.dart';
 import 'package:analyzer_plugin/channel/channel.dart';
@@ skipping 205 matching lines @@
 
   @override
   void close() {
     _receivePort?.close();
     _errorPort?.close();
     _exitPort?.close();
     _isolate = null;
   }
 
   @override
+  void kill() {
+    _isolate.kill(priority: Isolate.IMMEDIATE);
+  }
+
+  @override
   Future<Null> listen(void onResponse(Response response),
       void onNotification(Notification notification),
       {Function onError, void onDone()}) async {
     if (_isolate != null) {
       throw new StateError('Cannot listen to the same channel more than once.');
     }
     _receivePort = new ReceivePort();
     if (onError != null) {
       _errorPort = new ReceivePort();
       _errorPort.listen((error) {
@@ skipping 46 matching lines @@
     String encodedRequest = JSON.encode(json);
     instrumentationService.logPluginRequest(pluginId, encodedRequest);
     _sendPort.send(json);
   }
 
   /**
    * Spawn the isolate in which the plugin is running.
    */
   Future<Isolate> _spawnIsolate();
 }