Update //base to chromium 9659b08ea5a34f889dc4166217f438095ddc10d2

base/threading/post_task_and_reply_impl.h

 // Copyright (c) 2011 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 contains the implementation shared by
 // TaskRunner::PostTaskAndReply and WorkerPool::PostTaskAndReply.
 
 #ifndef BASE_THREADING_POST_TASK_AND_REPLY_IMPL_H_
 #define BASE_THREADING_POST_TASK_AND_REPLY_IMPL_H_
 
 #include "base/callback_forward.h"
 #include "base/location.h"
 
 namespace base {
 namespace internal {
 
 // Inherit from this in a class that implements PostTask appropriately
 // for sending to a destination thread.
 //
 // Note that 'reply' will always get posted back to your current
 // MessageLoop.
 //
 // If you're looking for a concrete implementation of
 // PostTaskAndReply, you probably want base::SingleThreadTaskRunner, or you
 // may want base::WorkerPool.
 class PostTaskAndReplyImpl {
  public:
+  virtual ~PostTaskAndReplyImpl() = default;
+
   // Implementation for TaskRunner::PostTaskAndReply and
   // WorkerPool::PostTaskAndReply.
   bool PostTaskAndReply(const tracked_objects::Location& from_here,
                         const Closure& task,
                         const Closure& reply);
 
  private:
   virtual bool PostTask(const tracked_objects::Location& from_here,
                         const Closure& task) = 0;
 };
 
 }  // namespace internal
 }  // namespace base
 
 #endif  // BASE_THREADING_POST_TASK_AND_REPLY_IMPL_H_