net: Make sure the FileStream file is closed on the worker thread.

net/base/file_stream_context.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 "net/base/file_stream_context.h"
 
 #include "base/location.h"
 #include "base/message_loop/message_loop_proxy.h"
 #include "base/task_runner_util.h"
 #include "base/threading/thread_restrictions.h"
@@ skipping 164 matching lines @@
   return OpenResult(file.Pass(), IOResult(OK, 0));
 }
 
 FileStream::Context::IOResult FileStream::Context::CloseFileImpl() {
   file_.Close();
   return IOResult(OK, 0);
 }
 
 void FileStream::Context::OnOpenCompleted(const CompletionCallback& callback,
                                           OpenResult open_result) {
-  if (open_result.file.IsValid() && !orphaned_) {
-    file_ = open_result.file.Pass();
+  file_ = open_result.file.Pass();
+  if (file_.IsValid() && !orphaned_)
     OnAsyncFileOpened();
-  }
+
   OnAsyncCompleted(IntToInt64(callback), open_result.error_code);
 }
 
 void FileStream::Context::CloseAndDelete() {
   DCHECK(!async_in_progress_);
 
   if (file_.IsValid()) {
     bool posted = task_runner_.get()->PostTask(
         FROM_HERE,
         base::Bind(base::IgnoreResult(&Context::CloseFileImpl),
@@ skipping 16 matching lines @@
   // should be reset before CloseAsync() because it shouldn't run if any async
   // operation is in progress.
   async_in_progress_ = false;
   if (orphaned_)
     CloseAndDelete();
   else
     callback.Run(result.result);
 }
 
 }  // namespace net