Fix filesystem.retainEntry API to handle non-native directory.

chrome/browser/extensions/api/file_system/file_system_api.h

 // Copyright (c) 2012 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_EXTENSIONS_API_FILE_SYSTEM_FILE_SYSTEM_API_H_
 #define CHROME_BROWSER_EXTENSIONS_API_FILE_SYSTEM_FILE_SYSTEM_API_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 167 matching lines @@
 
  protected:
   virtual ~FileSystemRetainEntryFunction() {}
   virtual bool RunAsync() override;
 
  private:
   // Retains the file entry referenced by |entry_id| in apps::SavedFilesService.
   // |entry_id| must refer to an entry in an isolated file system.
   void RetainFileEntry(const std::string& entry_id);
 
-  void SetIsDirectoryOnFileThread();
+  void SetIsDirectoryOnIOThread(const std::string& entry_id,

[mtomasz, 2014/10/14 06:08:50]

nit: Please add a comment.

[hirono, 2014/10/14 09:22:10]

I removed the method.

+                                base::File::Error result,
+                                const base::File::Info& file_info);
 
   // Whether the file being retained is a directory.
   bool is_directory_;
 
   // The path to the file to retain.
   base::FilePath path_;
 };
 
 class FileSystemIsRestorableFunction : public ChromeSyncExtensionFunction {
  public:
@@ skipping 40 matching lines @@
                              FILESYSTEM_GETOBSERVEDENTRIES);
 
  protected:
   virtual ~FileSystemGetObservedEntriesFunction() {}
   virtual bool RunSync() override;
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_API_FILE_SYSTEM_FILE_SYSTEM_API_H_