Removed fixed dependencies

packages/analyzer/lib/instrumentation/file_instrumentation.dart

Index: packages/analyzer/lib/instrumentation/file_instrumentation.dart
diff --git a/packages/analyzer/lib/instrumentation/file_instrumentation.dart b/packages/analyzer/lib/instrumentation/file_instrumentation.dart
index ba23b68f3b5dfe502e462f7d0410305daeac054d..d4088f87fd145cb493c5b0103c0462f3c53fdc1e 100644
--- a/packages/analyzer/lib/instrumentation/file_instrumentation.dart
+++ b/packages/analyzer/lib/instrumentation/file_instrumentation.dart
@@ -2,8 +2,9 @@
 // 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.
 
-library file_instrumentation;
+library analyzer.instrumentation.file_instrumentation;
 
+import 'dart:async';
 import 'dart:io';
 
 import 'package:analyzer/instrumentation/instrumentation.dart';
@@ -19,6 +20,9 @@ class FileInstrumentationServer implements InstrumentationServer {
     _sink = file.openWrite();
   }
 
+  @override
+  String get sessionId => '';
+
   @override
   void log(String message) {
     _sink.writeln(message);
@@ -30,8 +34,8 @@ class FileInstrumentationServer implements InstrumentationServer {
   }
 
   @override
-  void shutdown() {
-    _sink.close();
+  Future shutdown() async {
+    await _sink.close();
     _sink = null;
   }
 }