GTTF: Add missing virtual destructors.

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
 // MessageLoopProxy::PostTaskAndReply and WorkerPool::PostTaskAndReply.
 
 #ifndef BASE_THREADING_POST_TASK_AND_REPLY_IMPL_H_
 #define BASE_THREADING_POST_TASK_AND_REPLY_IMPL_H_
 
@@ skipping 13 matching lines @@
 // PostTaskAndReply, you probably want base::MessageLoopProxy, or you
 // may want base::WorkerPool.
 class PostTaskAndReplyImpl {
  public:
   // Implementation for MessageLoopProxy::PostTaskAndReply and
   // WorkerPool::PostTaskAndReply.
   bool PostTaskAndReply(const tracked_objects::Location& from_here,
                         const Closure& task,
                         const Closure& reply);
 
+ protected:
+  virtual ~PostTaskAndReplyImpl() { }
+
  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_