Objects that derive from RefCounted/RefCountedThreadSafe should not have public dtors.

webkit/dom_storage/dom_storage_task_runner.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 WEBKIT_DOM_STORAGE_DOM_STORAGE_TASK_RUNNER_
 #define WEBKIT_DOM_STORAGE_DOM_STORAGE_TASK_RUNNER_
 #pragma once
 
 #include "base/memory/ref_counted.h"
 #include "base/sequenced_task_runner.h"
@@ skipping 37 matching lines @@
   // Only here because base::TaskRunner requires it, the return
   // value is hard coded to true, do not rely on this method.
   virtual bool RunsTasksOnCurrentThread() const OVERRIDE;
 
   // DEPRECATED: Only here because base::TaskRunner requires it, implemented
   // by calling the virtual PostDelayedTask(..., TimeDelta) variant.
   virtual bool PostDelayedTask(
       const tracked_objects::Location& from_here,
       const base::Closure& task,
       int64 delay_ms) OVERRIDE;
+
+ protected:
+  virtual ~DomStorageTaskRunner() {}
 };
 
 // A derived class used in chromium that utilizes a SequenceWorkerPool
 // under dom_storage specific SequenceTokens. The |delayed_task_loop|
 // is used to delay scheduling on the worker pool.
 class DomStorageWorkerPoolTaskRunner : public DomStorageTaskRunner {
  public:
   DomStorageWorkerPoolTaskRunner(
       base::SequencedWorkerPool* sequenced_worker_pool,
       base::SequencedWorkerPool::SequenceToken primary_sequence_token,
       base::SequencedWorkerPool::SequenceToken commit_sequence_token,
       base::MessageLoopProxy* delayed_task_loop);
 
   virtual bool PostDelayedTask(
       const tracked_objects::Location& from_here,
       const base::Closure& task,
       base::TimeDelta delay) OVERRIDE;
 
   virtual bool PostShutdownBlockingTask(
       const tracked_objects::Location& from_here,
       SequenceID sequence_id,
       const base::Closure& task) OVERRIDE;
 
+ protected:
+  virtual ~DomStorageWorkerPoolTaskRunner();
+
  private:
-  virtual ~DomStorageWorkerPoolTaskRunner();
   const scoped_refptr<base::MessageLoopProxy> message_loop_;
   const scoped_refptr<base::SequencedWorkerPool> sequenced_worker_pool_;
   base::SequencedWorkerPool::SequenceToken primary_sequence_token_;
   base::SequencedWorkerPool::SequenceToken commit_sequence_token_;
 };
 
 // A derived class used in unit tests that ignores all delays so
 // we don't block in unit tests waiting for timeouts to expire.
 // There is no distinction between [non]-shutdown-blocking or
 // the primary sequence vs the commit sequence in the mock,
 // all tasks are scheduled on |message_loop| with zero delay.
 class MockDomStorageTaskRunner : public DomStorageTaskRunner {
  public:
   explicit MockDomStorageTaskRunner(base::MessageLoopProxy* message_loop);
 
   virtual bool PostDelayedTask(
       const tracked_objects::Location& from_here,
       const base::Closure& task,
       base::TimeDelta delay) OVERRIDE;
 
   virtual bool PostShutdownBlockingTask(
       const tracked_objects::Location& from_here,
       SequenceID sequence_id,
       const base::Closure& task) OVERRIDE;
 
+ protected:
+  virtual ~MockDomStorageTaskRunner();
+
  private:
-  virtual ~MockDomStorageTaskRunner();
   const scoped_refptr<base::MessageLoopProxy> message_loop_;
 };
 
 }  // namespace dom_storage
 
 #endif  // WEBKIT_DOM_STORAGE_DOM_STORAGE_TASK_RUNNER_