[fsp] Add support for closing files.

chrome/browser/chromeos/file_system_provider/operations/open_file.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 "chrome/browser/chromeos/file_system_provider/operations/open_file.h"
 
 #include <string>
 
 #include "chrome/common/extensions/api/file_system_provider.h"
 #include "chrome/common/extensions/api/file_system_provider_internal.h"
 
 namespace chromeos {
 namespace file_system_provider {
 namespace operations {
 
-OpenFile::OpenFile(extensions::EventRouter* event_router,
-                   const ProvidedFileSystemInfo& file_system_info,
-                   const base::FilePath& file_path,
-                   ProvidedFileSystemInterface::OpenFileMode mode,
-                   bool create,
-                   const fileapi::AsyncFileUtil::StatusCallback& callback)
+OpenFile::OpenFile(
+    extensions::EventRouter* event_router,
+    const ProvidedFileSystemInfo& file_system_info,
+    const base::FilePath& file_path,
+    ProvidedFileSystemInterface::OpenFileMode mode,
+    bool create,
+    const ProvidedFileSystemInterface::OpenFileCallback& callback)
     : Operation(event_router, file_system_info),
       file_path_(file_path),
       mode_(mode),
       create_(create),
       callback_(callback) {
 }
 
 OpenFile::~OpenFile() {
 }
 
@@ skipping 13 matching lines @@
   }
 
   values->AppendBoolean(create_);
 
   return SendEvent(
       request_id,
       extensions::api::file_system_provider::OnOpenFileRequested::kEventName,
       values.Pass());
 }
 
-void OpenFile::OnSuccess(int /* request_id */,
+void OpenFile::OnSuccess(int request_id,
                          scoped_ptr<RequestValue> result,
                          bool has_next) {
-  callback_.Run(base::File::FILE_OK);
+  // File handle is the same as request id of the OpenFile operation.
+  callback_.Run(request_id, base::File::FILE_OK);
 }
 
 void OpenFile::OnError(int /* request_id */, base::File::Error error) {
-  callback_.Run(error);
+  callback_.Run(0 /* file_handle */, error);
 }
 
 }  // namespace operations
 }  // namespace file_system_provider
 }  // namespace chromeos