replace NULL->nullptr in src/remoting.

remoting/host/policy_hack/policy_watcher_linux.cc

 // Copyright (c) 2012 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.
 
 // Most of this code is copied from various classes in
 // src/chrome/browser/policy. In particular, look at
 //
 //   file_based_policy_loader.{h,cc}
 //   config_dir_policy_provider.{h,cc}
 //
@@ skipping 107 matching lines @@
       if (base::GetFileInfo(config_file, &file_info) &&
           !file_info.is_directory) {
         last_modification = std::max(last_modification,
                                      file_info.last_modified);
       }
     }
 
     return last_modification;
   }
 
-  // Returns NULL if the policy dictionary couldn't be read.
+  // Returns nullptr if the policy dictionary couldn't be read.
   scoped_ptr<base::DictionaryValue> Load() {
     DCHECK(OnPolicyWatcherThread());
     // Enumerate the files and sort them lexicographically.
     std::set<base::FilePath> files;
     base::FileEnumerator file_enumerator(config_dir_, false,
                                          base::FileEnumerator::FILES);
     for (base::FilePath config_file_path = file_enumerator.Next();
          !config_file_path.empty(); config_file_path = file_enumerator.Next())
       files.insert(config_file_path);
 
@@ skipping 108 matching lines @@
 
 scoped_ptr<PolicyWatcher> PolicyWatcher::Create(
     policy::PolicyService* policy_service,
     scoped_refptr<base::SingleThreadTaskRunner> task_runner) {
   base::FilePath policy_dir(kPolicyDir);
   return make_scoped_ptr(new PolicyWatcherLinux(task_runner, policy_dir));
 }
 
 }  // namespace policy_hack
 }  // namespace remoting