Update from https://crrev.com/320343

base/threading/thread_local_storage.h

 // 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.
 
 #ifndef BASE_THREADING_THREAD_LOCAL_STORAGE_H_
 #define BASE_THREADING_THREAD_LOCAL_STORAGE_H_
 
 #include "base/base_export.h"
 #include "base/basictypes.h"
 
@@ skipping 118 matching lines @@
     // Calls StaticSlot::Initialize().
     explicit Slot(TLSDestructorFunc destructor = NULL);
 
    private:
     using StaticSlot::initialized_;
     using StaticSlot::slot_;
 
     DISALLOW_COPY_AND_ASSIGN(Slot);
   };
 
+ private:
   DISALLOW_COPY_AND_ASSIGN(ThreadLocalStorage);
 };
 
 }  // namespace base
 
 #endif  // BASE_THREADING_THREAD_LOCAL_STORAGE_H_