Require explicit selection of traits for LazyInstance

services/file/user_id_map.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "services/file/user_id_map.h"
 
 #include <map>
 
 #include "base/lazy_instance.h"
 
 namespace file {
 
 namespace {
-base::LazyInstance<std::map<std::string, base::FilePath>>
+base::LazyInstance<std::map<std::string, base::FilePath>>::DestructorAtExit
     g_user_id_to_data_dir = LAZY_INSTANCE_INITIALIZER;
 }  // namespace
 
 void AssociateServiceUserIdWithUserDir(const std::string& user_id,
                                        const base::FilePath& user_dir) {
   g_user_id_to_data_dir.Get()[user_id] = user_dir;
 }
 
 void ForgetServiceUserIdUserDirAssociation(const std::string& user_id) {
   auto it = g_user_id_to_data_dir.Get().find(user_id);
   if (it != g_user_id_to_data_dir.Get().end())
     g_user_id_to_data_dir.Get().erase(it);
 }
 
 base::FilePath GetUserDirForUserId(const std::string& user_id) {
   auto it = g_user_id_to_data_dir.Get().find(user_id);
   DCHECK(it != g_user_id_to_data_dir.Get().end());
   return it->second;
 }
 
 }  // namespace file