[fsp] First part of support for reading files.

chrome/browser/chromeos/file_system_provider/provided_file_system.h

 // 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.
 
 #ifndef CHROME_BROWSER_CHROMEOS_FILE_SYSTEM_PROVIDER_PROVIDED_FILE_SYSTEM_H_
 #define CHROME_BROWSER_CHROMEOS_FILE_SYSTEM_PROVIDER_PROVIDED_FILE_SYSTEM_H_
 
 #include "chrome/browser/chromeos/file_system_provider/provided_file_system_info.h"
 #include "chrome/browser/chromeos/file_system_provider/provided_file_system_interface.h"
 #include "chrome/browser/chromeos/file_system_provider/request_manager.h"
 #include "webkit/browser/fileapi/async_file_util.h"
 
+namespace net {
+class IOBuffer;
+}  // namespace net
+
 namespace base {
 class FilePath;
 }  // namespace base
 
 namespace extensions {
 class EventRouter;
 }  // namespace extensions
 
 namespace chromeos {
 namespace file_system_provider {
@@ skipping 15 matching lines @@
   virtual void ReadDirectory(
       const base::FilePath& directory_path,
       const fileapi::AsyncFileUtil::ReadDirectoryCallback& callback) OVERRIDE;
   virtual void OpenFile(const base::FilePath& file_path,
                         OpenFileMode mode,
                         bool create,
                         const OpenFileCallback& callback) OVERRIDE;
   virtual void CloseFile(
       int file_handle,
       const fileapi::AsyncFileUtil::StatusCallback& callback) OVERRIDE;
+  virtual void ReadFile(int file_handle,
+                        net::IOBuffer* buffer,
+                        int64 offset,
+                        int length,
+                        const ReadChunkReceivedCallback& callback) OVERRIDE;
   virtual const ProvidedFileSystemInfo& GetFileSystemInfo() const OVERRIDE;
   virtual RequestManager* GetRequestManager() OVERRIDE;
 
  private:
   extensions::EventRouter* event_router_;
   RequestManager request_manager_;
   ProvidedFileSystemInfo file_system_info_;
 
   DISALLOW_COPY_AND_ASSIGN(ProvidedFileSystem);
 };
 
 }  // namespace file_system_provider
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_FILE_SYSTEM_PROVIDER_PROVIDED_FILE_SYSTEM_H_