Pass Callback by value on PostTaskAndReply family

base/task/cancelable_task_tracker.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.
 
 // CancelableTaskTracker posts tasks (in the form of a Closure) to a
 // TaskRunner, and is able to cancel the task later if it's not needed
 // anymore.  On destruction, CancelableTaskTracker will cancel all
 // tracked tasks.
 //
 // Each cancelable task can be associated with a reply (also a Closure). After
@@ skipping 19 matching lines @@
 //    tasks. This is commonly used to cancel all outstanding tasks.
 //
 // 3. Both task and reply are deleted on the originating sequence.
 //
 // 4. IsCanceledCallback can be run or deleted on any sequence.
 #ifndef BASE_TASK_CANCELABLE_TASK_TRACKER_H_
 #define BASE_TASK_CANCELABLE_TASK_TRACKER_H_
 
 #include <stdint.h>
 
+#include <utility>
+
 #include "base/base_export.h"
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/containers/hash_tables.h"
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "base/post_task_and_reply_with_result_internal.h"
 #include "base/sequence_checker.h"
 
 namespace tracked_objects {
@@ skipping 17 matching lines @@
 
   // Cancels all tracked tasks.
   ~CancelableTaskTracker();
 
   TaskId PostTask(base::TaskRunner* task_runner,
                   const tracked_objects::Location& from_here,
                   const base::Closure& task);
 
   TaskId PostTaskAndReply(base::TaskRunner* task_runner,
                           const tracked_objects::Location& from_here,
-                          const base::Closure& task,
-                          const base::Closure& reply);
+                          base::Closure task,
+                          base::Closure reply);
 
   template <typename TaskReturnType, typename ReplyArgType>
-  TaskId PostTaskAndReplyWithResult(
-      base::TaskRunner* task_runner,
-      const tracked_objects::Location& from_here,
-      const base::Callback<TaskReturnType(void)>& task,
-      const base::Callback<void(ReplyArgType)>& reply) {
+  TaskId PostTaskAndReplyWithResult(base::TaskRunner* task_runner,
+                                    const tracked_objects::Location& from_here,
+                                    base::Callback<TaskReturnType()> task,
+                                    base::Callback<void(ReplyArgType)> reply) {
     TaskReturnType* result = new TaskReturnType();
     return PostTaskAndReply(
-        task_runner,
-        from_here,
+        task_runner, from_here,
         base::Bind(&base::internal::ReturnAsParamAdapter<TaskReturnType>,
-                   task,
-                   base::Unretained(result)),
+                   std::move(task), base::Unretained(result)),
         base::Bind(&base::internal::ReplyAdapter<TaskReturnType, ReplyArgType>,
-                   reply,
-                   base::Owned(result)));
+                   std::move(reply), base::Owned(result)));
   }
 
   // Creates a tracked TaskId and an associated IsCanceledCallback. Client can
   // later call TryCancel() with the returned TaskId, and run |is_canceled_cb|
   // from any thread to check whether the TaskId is canceled.
   //
   // The returned task ID is tracked until the last copy of
   // |is_canceled_cb| is destroyed.
   //
   // Note. This function is used to address some special cancelation requirement
@@ skipping 27 matching lines @@
   SequenceChecker sequence_checker_;
 
   base::WeakPtrFactory<CancelableTaskTracker> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(CancelableTaskTracker);
 };
 
 }  // namespace base
 
 #endif  // BASE_TASK_CANCELABLE_TASK_TRACKER_H_