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

base/test/test_mock_time_task_runner.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 BASE_TEST_TEST_MOCK_TIME_TASK_RUNNER_H_
 #define BASE_TEST_TEST_MOCK_TIME_TASK_RUNNER_H_
 
 #include <stddef.h>
 
 #include <deque>
 #include <memory>
 #include <queue>
 #include <vector>
 
+#include "base/callback.h"
 #include "base/callback_helpers.h"
 #include "base/macros.h"
 #include "base/single_thread_task_runner.h"
 #include "base/synchronization/lock.h"
 #include "base/test/test_pending_task.h"
 #include "base/threading/thread_checker_impl.h"
 #include "base/time/time.h"
 
 namespace base {
 
@@ skipping 108 matching lines @@
   std::unique_ptr<TickClock> GetMockTickClock() const;
 
   std::deque<TestPendingTask> TakePendingTasks();
   bool HasPendingTask() const;
   size_t GetPendingTaskCount() const;
   TimeDelta NextPendingTaskDelay() const;
 
   // SingleThreadTaskRunner:
   bool RunsTasksOnCurrentThread() const override;
   bool PostDelayedTask(const tracked_objects::Location& from_here,
-                       const Closure& task,
+                       Closure task,
                        TimeDelta delay) override;
   bool PostNonNestableDelayedTask(const tracked_objects::Location& from_here,
-                                  const Closure& task,
+                                  Closure task,
                                   TimeDelta delay) override;
 
  protected:
   ~TestMockTimeTaskRunner() override;
 
   // Whether the elapsing of virtual time is stopped or not. Subclasses can
   // override this method to perform early exits from a running task runner.
   // Defaults to always return false.
   virtual bool IsElapsingStopped();
 
@@ skipping 57 matching lines @@
   size_t next_task_ordinal_;
 
   Lock tasks_lock_;
 
   DISALLOW_COPY_AND_ASSIGN(TestMockTimeTaskRunner);
 };
 
 }  // namespace base
 
 #endif  // BASE_TEST_TEST_MOCK_TIME_TASK_RUNNER_H_