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

cc/test/ordered_simple_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 CC_TEST_ORDERED_SIMPLE_TASK_RUNNER_H_
 #define CC_TEST_ORDERED_SIMPLE_TASK_RUNNER_H_
 
 #include <stddef.h>
 
 #include <limits>
 #include <memory>
 #include <set>
 #include <vector>
 
+#include "base/callback.h"
 #include "base/compiler_specific.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/test/simple_test_tick_clock.h"
 #include "base/test/test_simple_task_runner.h"
 #include "base/threading/thread_checker.h"
 #include "base/trace_event/trace_event.h"
 
 namespace cc {
 
 // Subclass of TestPendingTask which has a unique ID for every task, supports
 // being used inside a std::set and has debug tracing support.
 class TestOrderablePendingTask : public base::TestPendingTask {
  public:
   TestOrderablePendingTask();
   TestOrderablePendingTask(const tracked_objects::Location& location,
-                           const base::Closure& task,
+                           base::Closure task,
                            base::TimeTicks post_time,
                            base::TimeDelta delay,
                            TestNestability nestability);
   TestOrderablePendingTask(TestOrderablePendingTask&&);
   ~TestOrderablePendingTask();
 
   TestOrderablePendingTask& operator=(TestOrderablePendingTask&&);
 
   // operators needed by std::set and comparison
   bool operator==(const TestOrderablePendingTask& other) const;
@@ skipping 14 matching lines @@
 
 // This runs pending tasks based on task's post_time + delay.
 // We should not execute a delayed task sooner than some of the queued tasks
 // which don't have a delay even though it is queued early.
 class OrderedSimpleTaskRunner : public base::SingleThreadTaskRunner {
  public:
   OrderedSimpleTaskRunner(base::SimpleTestTickClock* now_src, bool advance_now);
 
   // base::TestSimpleTaskRunner implementation:
   bool PostDelayedTask(const tracked_objects::Location& from_here,
-                       const base::Closure& task,
+                       base::Closure task,
                        base::TimeDelta delay) override;
   bool PostNonNestableDelayedTask(const tracked_objects::Location& from_here,
-                                  const base::Closure& task,
+                                  base::Closure task,
                                   base::TimeDelta delay) override;
 
   bool RunsTasksOnCurrentThread() const override;
 
   static base::TimeTicks AbsoluteMaxNow();
 
   // Set a maximum number of tasks to run at once. Useful as a timeout to
   // prevent infinite task loops.
   static const size_t kAbsoluteMaxTasks;
   void SetRunTaskLimit(size_t max_tasks) { max_tasks_ = max_tasks; }
@@ skipping 79 matching lines @@
   bool inside_run_tasks_until_;
   std::set<TestOrderablePendingTask> pending_tasks_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(OrderedSimpleTaskRunner);
 };
 
 }  // namespace cc
 
 #endif  // CC_TEST_ORDERED_SIMPLE_TASK_RUNNER_H_