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

media/cast/test/skewed_single_thread_task_runner.h

 // Copyright 2014 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 MEDIA_CAST_TEST_SKEWED_SINGLE_THREAD_TASK_RUNNER_H_
 #define MEDIA_CAST_TEST_SKEWED_SINGLE_THREAD_TASK_RUNNER_H_
 
 #include <map>
 
+#include "base/callback.h"
 #include "base/macros.h"
 #include "base/single_thread_task_runner.h"
 #include "base/test/simple_test_tick_clock.h"
 #include "base/test/test_pending_task.h"
 
 namespace media {
 namespace cast {
 namespace test {
 
 // This class wraps a SingleThreadTaskRunner, and allows you to scale
 // the delay for any posted task by a factor. The factor is changed by
 // calling SetSkew(). A skew of 2.0 means that all delayed task will
 // have to wait twice as long.
 class SkewedSingleThreadTaskRunner : public base::SingleThreadTaskRunner {
  public:
   explicit SkewedSingleThreadTaskRunner(
       const scoped_refptr<base::SingleThreadTaskRunner>& task_runner);
 
   // Set the delay multiplier to |skew|.
   void SetSkew(double skew);
 
   // base::SingleThreadTaskRunner implementation.
   bool PostDelayedTask(const tracked_objects::Location& from_here,
-                       const base::Closure& task,
+                       base::Closure task,
                        base::TimeDelta delay) final;
 
   bool RunsTasksOnCurrentThread() const final;
 
   // This function is currently not used, and will return false.
   bool PostNonNestableDelayedTask(const tracked_objects::Location& from_here,
-                                  const base::Closure& task,
+                                  base::Closure task,
                                   base::TimeDelta delay) final;
 
  protected:
   ~SkewedSingleThreadTaskRunner() final;
 
  private:
   double skew_;
   scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
 
   DISALLOW_COPY_AND_ASSIGN(SkewedSingleThreadTaskRunner);
 };
 
 }  // namespace test
 }  // namespace cast
 }  // namespace media
 
 #endif  // MEDIA_CAST_TEST_SKEWED_SINGLE_THREAD_TASK_RUNNER_H_