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 164 matching lines @@
 class FileSystemRetainEntryFunction : public ChromeAsyncExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileSystem.retainEntry", FILESYSTEM_RETAINENTRY)
 
  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();
-
-  // Whether the file being retained is a directory.
-  bool is_directory_;
-
-  // The path to the file to retain.
-  base::FilePath path_;
+  // |entry_id| must refer to an entry in an isolated file system.  |path| is a
+  // path of the entry.  |file_info| is base::File::Info of the entry if it can
+  // be obtained.
+  void RetainFileEntry(const std::string& entry_id,
+                       const base::FilePath& path,
+                       scoped_ptr<base::File::Info> file_info);
 };
 
 class FileSystemIsRestorableFunction : public ChromeSyncExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileSystem.isRestorable", FILESYSTEM_ISRESTORABLE)
 
  protected:
   virtual ~FileSystemIsRestorableFunction() {}
   virtual bool RunSync() override;
 };
@@ skipping 34 matching lines @@
                              FILESYSTEM_GETOBSERVEDENTRIES);
 
  protected:
   virtual ~FileSystemGetObservedEntriesFunction() {}
   virtual bool RunSync() override;
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_API_FILE_SYSTEM_FILE_SYSTEM_API_H_