[fsp] Fix crash when reading files.

chrome/browser/chromeos/file_system_provider/operations/read_file.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_OPERATIONS_READ_FILE_H_
 #define CHROME_BROWSER_CHROMEOS_FILE_SYSTEM_PROVIDER_OPERATIONS_READ_FILE_H_
 
 #include "base/files/file.h"
+#include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "chrome/browser/chromeos/file_system_provider/operations/operation.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_value.h"
 #include "net/base/io_buffer.h"
 #include "webkit/browser/fileapi/async_file_util.h"
 
 namespace base {
 class FilePath;
 }  // namespace base
 
 namespace extensions {
 class EventRouter;
 }  // namespace extensions
 
 namespace chromeos {
 namespace file_system_provider {
 namespace operations {
 
 // Bridge between fileapi read file and providing extension's read fil request.
 // Created per request.
 class ReadFile : public Operation {
  public:
   ReadFile(
       extensions::EventRouter* event_router,
       const ProvidedFileSystemInfo& file_system_info,
       int file_handle,
-      net::IOBuffer* buffer,
+      scoped_refptr<net::IOBuffer> buffer,
       int64 offset,
       int length,
       const ProvidedFileSystemInterface::ReadChunkReceivedCallback& callback);
   virtual ~ReadFile();
 
   // Operation overrides.
   virtual bool Execute(int request_id) OVERRIDE;
   virtual void OnSuccess(int request_id,
                          scoped_ptr<RequestValue> result,
                          bool has_next) OVERRIDE;
   virtual void OnError(int request_id, base::File::Error error) OVERRIDE;
 
  private:
   int file_handle_;
-  net::IOBuffer* buffer_;
+  scoped_refptr<net::IOBuffer> buffer_;
   int64 offset_;
   int length_;
   int64 current_offset_;
   const ProvidedFileSystemInterface::ReadChunkReceivedCallback callback_;
 
   DISALLOW_COPY_AND_ASSIGN(ReadFile);
 };
 
 }  // namespace operations
 }  // namespace file_system_provider
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_FILE_SYSTEM_PROVIDER_OPERATIONS_READ_FILE_H_