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

base/test/null_task_runner.cc

 // 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.
 
 #include "base/test/null_task_runner.h"
 
 namespace base {
 
 NullTaskRunner::NullTaskRunner() {}
 
 NullTaskRunner::~NullTaskRunner() {}
 
-bool NullTaskRunner::PostDelayedTask(
-    const tracked_objects::Location& from_here,
-    const base::Closure& task,
-    base::TimeDelta delay) {
+bool NullTaskRunner::PostDelayedTask(const tracked_objects::Location& from_here,
+                                     Closure task,
+                                     base::TimeDelta delay) {
   return false;
 }
 
 bool NullTaskRunner::PostNonNestableDelayedTask(
     const tracked_objects::Location& from_here,
-    const base::Closure& task,
+    Closure task,
     base::TimeDelta delay) {
   return false;
 }
 
 bool NullTaskRunner::RunsTasksOnCurrentThread() const {
   return true;
 }
 
 }  // namespace base