Remove more libraries directives from server

pkg/analysis_server/lib/src/status/tree_writer.dart

Index: pkg/analysis_server/lib/src/status/tree_writer.dart
diff --git a/pkg/analysis_server/lib/src/status/tree_writer.dart b/pkg/analysis_server/lib/src/status/tree_writer.dart
index 65e2cb037d83f9b69393005913feb0bf7145de89..e6b45709578c85a541ee76af77df86132448aa8e 100644
--- a/pkg/analysis_server/lib/src/status/tree_writer.dart
+++ b/pkg/analysis_server/lib/src/status/tree_writer.dart
@@ -2,8 +2,6 @@
 // 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 analysis_server.src.status.tree_writer;
-
 import 'dart:convert';
 
 import 'package:analyzer/exception/exception.dart';