Refactor History's CommitLaterTask with CancelableCallback

base/task/cancelable_task_tracker.cc

 // 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.
 
 #include "base/task/cancelable_task_tracker.h"
 
 #include <stddef.h>
 
 #include <utility>
 
@@ skipping 86 matching lines @@
                                          reply,
                                          untrack_closure));
 
   if (!success)
     return kBadTaskId;
 
   Track(id, flag);
   return id;
 }
 
+CancelableTaskTracker::TaskId CancelableTaskTracker::PostDelayedTask(

[Marc Treib, 2017/02/02 10:52:21]

Hm, I guess this is juuust different enough from PostTaskAndReply that it
doesn't make sense to share code :-/

[mastiz, 2017/02/02 12:35:53]

Acknowledged, I think so.

+    base::TaskRunner* task_runner,
+    const tracked_objects::Location& from_here,
+    const base::Closure& task,
+    base::TimeDelta delay) {
+  DCHECK(sequence_checker_.CalledOnValidSequence());
+
+  // Owned by callback below.
+  CancellationFlag* flag = new CancellationFlag();
+
+  TaskId id = next_id_;
+  next_id_++;  // int64_t is big enough that we ignore the potential overflow.
+
+  const Closure& untrack_closure =
+      Bind(&CancelableTaskTracker::Untrack, weak_factory_.GetWeakPtr(), id);
+  bool success = task_runner->PostDelayedTask(
+      from_here, Bind(&RunIfNotCanceledThenUntrack, base::Owned(flag), task,
+                      untrack_closure),
+      delay);
+
+  if (!success)
+    return kBadTaskId;
+
+  Track(id, flag);
+  return id;
+}
+
 CancelableTaskTracker::TaskId CancelableTaskTracker::NewTrackedTaskId(
     IsCanceledCallback* is_canceled_cb) {
   DCHECK(sequence_checker_.CalledOnValidSequence());
   DCHECK(base::SequencedTaskRunnerHandle::IsSet());
 
   TaskId id = next_id_;
   next_id_++;  // int64_t is big enough that we ignore the potential overflow.
 
   // Will be deleted by |untrack_and_delete_flag| after Untrack().
   CancellationFlag* flag = new CancellationFlag();
@@ skipping 56 matching lines @@
   DCHECK(success);
 }
 
 void CancelableTaskTracker::Untrack(TaskId id) {
   DCHECK(sequence_checker_.CalledOnValidSequence());
   size_t num = task_flags_.erase(id);
   DCHECK_EQ(1u, num);
 }
 
 }  // namespace base