[fsp] Add FileStreamReader for the reading operation.

chrome/browser/chromeos/file_system_provider/provided_file_system.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/provided_file_system.h"
 
 #include "base/files/file.h"
 #include "chrome/browser/chromeos/file_system_provider/operations/close_file.h"
 #include "chrome/browser/chromeos/file_system_provider/operations/get_metadata.h"
 #include "chrome/browser/chromeos/file_system_provider/operations/open_file.h"
 #include "chrome/browser/chromeos/file_system_provider/operations/read_directory.h"
 #include "chrome/browser/chromeos/file_system_provider/operations/read_file.h"
 #include "chrome/browser/chromeos/file_system_provider/operations/unmount.h"
 #include "chrome/browser/chromeos/file_system_provider/request_manager.h"
 #include "chrome/common/extensions/api/file_system_provider.h"
 #include "extensions/browser/event_router.h"
 
+namespace net {
+class IOBuffer;
+}  // namespace net
+
 namespace chromeos {
 namespace file_system_provider {
 
 ProvidedFileSystem::ProvidedFileSystem(
     extensions::EventRouter* event_router,
     const ProvidedFileSystemInfo& file_system_info)
-    : event_router_(event_router), file_system_info_(file_system_info) {
+    : event_router_(event_router),
+      file_system_info_(file_system_info),
+      weak_ptr_factory_(this) {
 }
 
 ProvidedFileSystem::~ProvidedFileSystem() {}
 
 void ProvidedFileSystem::RequestUnmount(
     const fileapi::AsyncFileUtil::StatusCallback& callback) {
   if (!request_manager_.CreateRequest(
           scoped_ptr<RequestManager::HandlerInterface>(new operations::Unmount(
               event_router_, file_system_info_, callback)))) {
     callback.Run(base::File::FILE_ERROR_SECURITY);
@@ skipping 78 matching lines @@
 }
 
 const ProvidedFileSystemInfo& ProvidedFileSystem::GetFileSystemInfo() const {
   return file_system_info_;
 }
 
 RequestManager* ProvidedFileSystem::GetRequestManager() {
   return &request_manager_;
 }
 
+base::WeakPtr<ProvidedFileSystemInterface> ProvidedFileSystem::GetWeakPtr() {
+  return weak_ptr_factory_.GetWeakPtr();
+}
+
 }  // namespace file_system_provider
 }  // namespace chromeos