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

net/quic/test_tools/test_task_runner.h

 // Copyright (c) 2012 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.
 //
 // Common utilities for Quic tests
 
 #ifndef NET_QUIC_TEST_TOOLS_TEST_TASK_RUNNER_H_
 #define NET_QUIC_TEST_TOOLS_TEST_TASK_RUNNER_H_
 
 #include <vector>
 
+#include "base/callback.h"
 #include "base/macros.h"
 #include "base/task_runner.h"
 #include "base/test/test_pending_task.h"
 
 namespace net {
 
 class MockClock;
 
 namespace test {
 
 typedef base::TestPendingTask PostedTask;
 
 class TestTaskRunner : public base::TaskRunner {
  public:
   explicit TestTaskRunner(MockClock* clock);
 
   // base::TaskRunner implementation.
   bool PostDelayedTask(const tracked_objects::Location& from_here,
-                       const base::Closure& task,
+                       base::Closure task,
                        base::TimeDelta delay) override;
   bool RunsTasksOnCurrentThread() const override;
 
   const std::vector<PostedTask>& GetPostedTasks() const;
 
   void RunNextTask();
 
  protected:
   ~TestTaskRunner() override;
 
  private:
   std::vector<PostedTask>::iterator FindNextTask();
 
   MockClock* const clock_;
   std::vector<PostedTask> tasks_;
 
   DISALLOW_COPY_AND_ASSIGN(TestTaskRunner);
 };
 
 }  // namespace test
 
 }  // namespace net
 
 #endif  // NET_QUIC_TEST_TOOLS_TEST_TASK_RUNNER_H_