Follow-up to https://codereview.chromium.org/291993003/

base/atomicops_internals_tsan.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.
 
 // This file is an internal atomic implementation for compiler-based
 // ThreadSanitizer. Use base/atomicops.h instead.
 
 #ifndef BASE_ATOMICOPS_INTERNALS_TSAN_H_
 #define BASE_ATOMICOPS_INTERNALS_TSAN_H_
 
 #include "base/base_export.h"
 
 // This struct is not part of the public API of this module; clients may not
 // use it.  (However, it's exported via BASE_EXPORT because clients implicitly
 // do use it at link time by inlining these functions.)
 // Features of this x86.  Values may not be correct before main() is run,
 // but are set conservatively.
 struct AtomicOps_x86CPUFeatureStruct {
   bool has_amd_lock_mb_bug;  // Processor has AMD memory-barrier bug; do lfence
                              // after acquire compare-and-swap.
-  bool has_sse2;             // Processor has SSE2.
 };
 BASE_EXPORT extern struct AtomicOps_x86CPUFeatureStruct
     AtomicOps_Internalx86CPUFeatures;
 
 #define ATOMICOPS_COMPILER_BARRIER() __asm__ __volatile__("" : : : "memory")
 
 #include <sanitizer/tsan_interface_atomic.h>
 
 namespace base {
 namespace subtle {
@@ skipping 164 matching lines @@
 inline void MemoryBarrier() {
   __tsan_atomic_thread_fence(__tsan_memory_order_seq_cst);
 }
 
 }  // namespace base::subtle
 }  // namespace base
 
 #undef ATOMICOPS_COMPILER_BARRIER
 
 #endif  // BASE_ATOMICOPS_INTERNALS_TSAN_H_