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

base/threading/worker_pool_posix.h

Index: base/threading/worker_pool_posix.h
diff --git a/base/threading/worker_pool_posix.h b/base/threading/worker_pool_posix.h
index f56582de3b57fd8611a42bdf71a75e109429cd16..eca113a8791cfbaff7ff9730455d5dbceba50096 100644
--- a/base/threading/worker_pool_posix.h
+++ b/base/threading/worker_pool_posix.h
@@ -53,7 +53,6 @@ class BASE_EXPORT PosixDynamicThreadPool
   // |idle_seconds_before_exit|.
   PosixDynamicThreadPool(const std::string& name_prefix,
                          int idle_seconds_before_exit);
-  ~PosixDynamicThreadPool();
 
   // Indicates that the thread pool is going away.  Stops handing out tasks to
   // worker threads.  Wakes up all the idle threads to let them exit.
@@ -68,8 +67,11 @@ class BASE_EXPORT PosixDynamicThreadPool
   PendingTask WaitForTask();
 
  private:
+  friend class RefCountedThreadSafe<PosixDynamicThreadPool>;
   friend class PosixDynamicThreadPoolPeer;
 
+  ~PosixDynamicThreadPool();
+
   // Adds pending_task to the thread pool.  This function will clear
   // |pending_task->task|.
   void AddTask(PendingTask* pending_task);