Introduce concurrent on-stack replacement.

src/platform/mutex.h

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 196 matching lines @@
 
 template <typename Mutex>
 class LockGuard V8_FINAL {
  public:
   explicit LockGuard(Mutex* mutex) : mutex_(mutex) { mutex_->Lock(); }
   ~LockGuard() { mutex_->Unlock(); }
 
  private:
   Mutex* mutex_;
 
-  LockGuard(const LockGuard<Mutex>& other) V8_DELETE;
-  LockGuard<Mutex>& operator=(const LockGuard<Mutex>& other) V8_DELETE;
+  DISALLOW_COPY_AND_ASSIGN(LockGuard);
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_PLATFORM_MUTEX_H_