[fsp] Let extensions decide about the file system id.

chrome/browser/chromeos/file_manager/volume_manager.cc

 // Copyright 2013 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.
 
 #include "chrome/browser/chromeos/file_manager/volume_manager.h"
 
 #include "base/basictypes.h"
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/command_line.h"
@@ skipping 221 matching lines @@
 std::string GetMountPointNameForMediaStorage(
     const storage_monitor::StorageInfo& info) {
   std::string name(kFileManagerMTPMountNamePrefix);
   name += info.device_id();
   return name;
 }
 
 }  // namespace
 
 VolumeInfo::VolumeInfo()
-    : file_system_id(0),
-      type(VOLUME_TYPE_GOOGLE_DRIVE),
+    : type(VOLUME_TYPE_GOOGLE_DRIVE),
       device_type(chromeos::DEVICE_TYPE_UNKNOWN),
       mount_condition(chromeos::disks::MOUNT_CONDITION_NONE),
       is_parent(false),
-      is_read_only(false) {}
+      is_read_only(false) {
+}
 
 VolumeInfo::~VolumeInfo() {
 }
 
 VolumeManager::VolumeManager(
     Profile* profile,
     drive::DriveIntegrationService* drive_integration_service,
     chromeos::PowerManagerClient* power_manager_client,
     chromeos::disks::DiskMountManager* disk_mount_manager,
     chromeos::file_system_provider::Service* file_system_provider_service)
@@ skipping 584 matching lines @@
     return;
   if (error_code == chromeos::MOUNT_ERROR_NONE)
     mounted_volumes_.erase(volume_info.volume_id);
 
   FOR_EACH_OBSERVER(VolumeManagerObserver,
                     observers_,
                     OnVolumeUnmounted(error_code, volume_info));
 }
 
 }  // namespace file_manager