Replace Closure in TaskRunner::PostTask with OneShotCallback

base/files/important_file_writer.cc

Index: base/files/important_file_writer.cc
diff --git a/base/files/important_file_writer.cc b/base/files/important_file_writer.cc
index edd400ce183f13fada7f89ad861c95e5510f7d55..973e3c2bdf10324ac74498f2f4f6a7e6ef96a04a 100644
--- a/base/files/important_file_writer.cc
+++ b/base/files/important_file_writer.cc
@@ -209,7 +209,7 @@ void ImportantFileWriter::RegisterOnNextSuccessfulWriteCallback(
   on_next_successful_write_ = on_next_successful_write;
 }
 
-bool ImportantFileWriter::PostWriteTask(const Callback<bool()>& task) {
+bool ImportantFileWriter::PostWriteTask(OnceCallback<bool()> task) {
   // TODO(gab): This code could always use PostTaskAndReplyWithResult and let
   // ForwardSuccessfulWrite() no-op if |on_next_successful_write_| is null, but
   // PostTaskAndReply causes memory leaks in tests (crbug.com/371974) and
@@ -217,15 +217,13 @@ bool ImportantFileWriter::PostWriteTask(const Callback<bool()>& task) {
   // using PostTask() in the typical scenario below.
   if (!on_next_successful_write_.is_null()) {
     return PostTaskAndReplyWithResult(
-        task_runner_.get(),
-        FROM_HERE,
-        MakeCriticalClosure(task),
+        task_runner_.get(), FROM_HERE, MakeCriticalClosure(std::move(task)),
         Bind(&ImportantFileWriter::ForwardSuccessfulWrite,
              weak_factory_.GetWeakPtr()));
   }
   return task_runner_->PostTask(
       FROM_HERE,
-      MakeCriticalClosure(Bind(IgnoreResult(task))));
+      MakeCriticalClosure(BindOnce(IgnoreResult(std::move(task)))));
 }
 
 void ImportantFileWriter::ForwardSuccessfulWrite(bool result) {