Replace Closure in TaskRunner::PostTask with OneShotCallback

cc/test/ordered_simple_task_runner.h

Index: cc/test/ordered_simple_task_runner.h
diff --git a/cc/test/ordered_simple_task_runner.h b/cc/test/ordered_simple_task_runner.h
index 9620a96058df422e00c841a5512bca675422d9f0..21d1b5cde1bc79c097c85d6e1b9370e6ffacf7ba 100644
--- a/cc/test/ordered_simple_task_runner.h
+++ b/cc/test/ordered_simple_task_runner.h
@@ -27,8 +27,9 @@ namespace cc {
 class TestOrderablePendingTask : public base::TestPendingTask {
  public:
   TestOrderablePendingTask();
+  TestOrderablePendingTask(TestOrderablePendingTask&&);
   TestOrderablePendingTask(const tracked_objects::Location& location,
-                           const base::Closure& task,
+                           base::OnceClosure task,
                            base::TimeTicks post_time,
                            base::TimeDelta delay,
                            TestNestability nestability);
@@ -42,6 +43,8 @@ class TestOrderablePendingTask : public base::TestPendingTask {
   std::unique_ptr<base::trace_event::ConvertableToTraceFormat> AsValue() const;
   void AsValueInto(base::trace_event::TracedValue* state) const;
 
+  size_t task_id() const { return task_id_; }
+
  private:
   static size_t task_id_counter;
   const size_t task_id_;
@@ -56,10 +59,10 @@ class OrderedSimpleTaskRunner : public base::SingleThreadTaskRunner {
 
   // base::TestSimpleTaskRunner implementation:
   bool PostDelayedTask(const tracked_objects::Location& from_here,
-                       const base::Closure& task,
+                       base::OnceClosure task,
                        base::TimeDelta delay) override;
   bool PostNonNestableDelayedTask(const tracked_objects::Location& from_here,
-                                  const base::Closure& task,
+                                  base::OnceClosure task,
                                   base::TimeDelta delay) override;
 
   bool RunsTasksOnCurrentThread() const override;
@@ -132,8 +135,7 @@ class OrderedSimpleTaskRunner : public base::SingleThreadTaskRunner {
 
  protected:
   static bool TaskRunCountBelowCallback(size_t max_tasks, size_t* task_run);
-  bool TaskExistedInitiallyCallback(
-      const std::set<TestOrderablePendingTask>& existing_tasks);
+  bool TaskExistedInitiallyCallback(const std::set<size_t>& existing_tasks);
   bool NowBeforeCallback(base::TimeTicks stop_at);
   bool AdvanceNowCallback();