Pass Callback to TaskRunner by value and consume it on invocation (1)

content/public/child/worker_thread.h

 // Copyright 2015 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 CONTENT_PUBLIC_CHILD_WORKER_THREAD_H_
 #define CONTENT_PUBLIC_CHILD_WORKER_THREAD_H_
 
 #include "base/callback.h"
 #include "base/macros.h"
 #include "content/common/content_export.h"
@@ skipping 24 matching lines @@
   // that worker's thread.
   static void AddObserver(Observer* observer);
   static void RemoveObserver(Observer* observer);
 
   // Returns the thread ID for the current worker thread, or 0 if this is not a
   // worker thread (for example, the render thread). Worker thread IDs will
   // always be > 0.
   static int GetCurrentId();
 
   // Posts a task to the worker thread with ID |id|. ID must be > 0.
-  static void PostTask(int id, const base::Closure& task);
+  static void PostTask(int id, base::Closure task);
 
  private:
   WorkerThread(){};
   DISALLOW_COPY_AND_ASSIGN(WorkerThread);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_CHILD_WORKER_THREAD_H_