Move spin_lock into partition_allocator.

base/allocator/partition_allocator/spin_lock.h

 // Copyright (c) 2013 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_SYNCHRONIZATION_SPIN_LOCK_H
-#define BASE_SYNCHRONIZATION_SPIN_LOCK_H
+#ifndef BASE_ALLOCATOR_PARTITION_ALLOCATOR_SPIN_LOCK_H
+#define BASE_ALLOCATOR_PARTITION_ALLOCATOR_SPIN_LOCK_H
 
 #include <atomic>
 #include <memory>
 #include <mutex>
 
 #include "base/base_export.h"
 #include "base/compiler_specific.h"
 
 // Spinlock is a simple spinlock class based on the standard CPU primitive of
 // atomic increment and decrement of an int at a given memory address. These are
@@ skipping 25 matching lines @@
   // This is called if the initial attempt to acquire the lock fails. It's
   // slower, but has a much better scheduling and power consumption behavior.
   BASE_EXPORT void LockSlow();
 
   std::atomic_int lock_;
 };
 
 }  // namespace subtle
 }  // namespace base
 
-#endif  // BASE_SYNCHRONIZATION_SPIN_LOCK_H
+#endif  // BASE_ALLOCATOR_PARTITION_ALLOCATOR_SPIN_LOCK_H