[fsp] Refactor handling operations.

chrome/browser/chromeos/file_system_provider/provided_file_system_interface.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_INTERFACE_H_
 #define CHROME_BROWSER_CHROMEOS_FILE_SYSTEM_PROVIDER_PROVIDED_FILE_SYSTEM_INTERFACE_H_
 
 #include "webkit/browser/fileapi/async_file_util.h"
 
 class EventRouter;
 
+namespace base {
+class FilePath;
+}  // namespace base
+
 namespace chromeos {
 namespace file_system_provider {
 
 class ProvidedFileSystemInfo;
 class RequestManager;
 
 // Interface for a provided file system. Acts as a proxy between providers
 // and clients.
 // TODO(mtomasz): Add more methods once implemented.
 class ProvidedFileSystemInterface {
  public:
   virtual ~ProvidedFileSystemInterface() {}
 
   // Requests unmounting of the file system. The callback is called when the
-  // request is accepted or rejected, with an error code. Returns false if the
-  // request could not been created, true otherwise.
-  virtual bool RequestUnmount(
+  // request is accepted or rejected, with an error code.
+  virtual void RequestUnmount(
       const fileapi::AsyncFileUtil::StatusCallback& callback) = 0;
 
   // Returns a provided file system info for this file system.
   virtual const ProvidedFileSystemInfo& GetFileSystemInfo() const = 0;
 
   // Returns a request manager for the file system.
   virtual RequestManager* GetRequestManager() = 0;
 };
 
 }  // namespace file_system_provider
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_FILE_SYSTEM_PROVIDER_PROVIDED_FILE_SYSTEM_INTERFACE_H_