Get rid of all the library tags.

lib/src/runner/hack_load_vm_file_hook.dart

 // Copyright (c) 2015, 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.
 
-library test.runner.hack_load_vm_file_hook;
-
 import 'dart:async';
 
 import '../backend/metadata.dart';
 import 'configuration.dart';
 import 'runner_suite.dart';
 
 typedef Future<RunnerSuite> LoadVMFileHook(String path, Metadata metadata,
     Configuration config);
 
 /// **Do not set or use this function without express permission from the test
 /// package authors**.
 ///
 /// A function that overrides the loader's default behavior for loading test
 /// suites on the Dart VM. This function takes the path to the file, the
 /// file's metadata, and the test runner's configuration and returns a
 /// [RunnerSuite] for that file.
 LoadVMFileHook loadVMFileHook;