Reland: URLRequestJob: change ReadRawData contract

chrome/browser/chromeos/fileapi/external_file_url_request_job.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_FILEAPI_EXTERNAL_FILE_URL_REQUEST_JOB_H_
 #define CHROME_BROWSER_CHROMEOS_FILEAPI_EXTERNAL_FILE_URL_REQUEST_JOB_H_
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 45 matching lines @@
   ExternalFileURLRequestJob(void* profile_id,
                             net::URLRequest* request,
                             net::NetworkDelegate* network_delegate);
 
   // net::URLRequestJob overrides:
   void SetExtraRequestHeaders(const net::HttpRequestHeaders& headers) override;
   void Start() override;
   void Kill() override;
   bool GetMimeType(std::string* mime_type) const override;
   bool IsRedirectResponse(GURL* location, int* http_status_code) override;
-  bool ReadRawData(net::IOBuffer* buf, int buf_size, int* bytes_read) override;
+  int ReadRawData(net::IOBuffer* buf, int buf_size) override;
 
  protected:
   ~ExternalFileURLRequestJob() override;
 
  private:
+  // Helper method to start the job. Should be called asynchronously because
+  // NotifyStartError() is not legal to call synchronously in
+  // URLRequestJob::Start().
+  void StartAsync();
+
   // Called from an internal helper class defined in drive_url_request_job.cc,
   // which is running on the UI thread.
   void OnHelperResultObtained(
       net::Error error,
       const scoped_refptr<storage::FileSystemContext>& file_system_context,
       scoped_ptr<IsolatedFileSystemScope> isolated_file_system_scope,
       const storage::FileSystemURL& file_system_url,
       const std::string& mime_type);
 
   // Called from FileSystemBackend::GetRedirectURLForContents.
   void OnRedirectURLObtained(const GURL& redirect_url);
 
   // Called from DriveURLRequestJob::OnFileInfoObtained.
   void OnFileInfoObtained(base::File::Error result,
                           const base::File::Info& file_info);
 
   // Called when DriveFileStreamReader::Read is completed.
   void OnReadCompleted(int read_result);
 
   void* const profile_id_;
 
   // The range of the file to be returned.
+  net::Error range_parse_result_;
   net::HttpByteRange byte_range_;
   int64 remaining_bytes_;
 
   scoped_refptr<storage::FileSystemContext> file_system_context_;
   scoped_ptr<IsolatedFileSystemScope> isolated_file_system_scope_;
   storage::FileSystemURL file_system_url_;
   std::string mime_type_;
   scoped_ptr<storage::FileStreamReader> stream_reader_;
   GURL redirect_url_;
 
   // This should remain the last member so it'll be destroyed first and
   // invalidate its weak pointers before other members are destroyed.
   base::WeakPtrFactory<ExternalFileURLRequestJob> weak_ptr_factory_;
   DISALLOW_COPY_AND_ASSIGN(ExternalFileURLRequestJob);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_FILEAPI_EXTERNAL_FILE_URL_REQUEST_JOB_H_