Reverting 27389.

base/ref_counted.h

 // Copyright (c) 2006-2008 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_REF_COUNTED_H_
 #define BASE_REF_COUNTED_H_
 
 #include "base/atomic_ref_count.h"
 #include "base/thread_collision_warner.h"
 
 namespace base {
 
 namespace subtle {
 
 class RefCountedBase {
  public:
+  static bool ImplementsThreadSafeReferenceCounting() { return false; }
+
   bool HasOneRef() const { return ref_count_ == 1; }
 
  protected:
   RefCountedBase();
   ~RefCountedBase();
 
   void AddRef();
 
   // Returns true if the object should self-delete.
   bool Release();
 
  private:
   int ref_count_;
 #ifndef NDEBUG
   bool in_dtor_;
 #endif
 
   DFAKE_MUTEX(add_release_);
 
   DISALLOW_COPY_AND_ASSIGN(RefCountedBase);
 };
 
 class RefCountedThreadSafeBase {
  public:
+  static bool ImplementsThreadSafeReferenceCounting() { return true; }
+
   bool HasOneRef() const;
 
  protected:
   RefCountedThreadSafeBase();
   ~RefCountedThreadSafeBase();
 
   void AddRef();
 
   // Returns true if the object should self-delete.
   bool Release();
@@ skipping 188 matching lines @@
 
   void swap(scoped_refptr<T>& r) {
     swap(&r.ptr_);
   }
 
  protected:
   T* ptr_;
 };
 
 #endif  // BASE_REF_COUNTED_H_