Regularize storage monitor creation in Windows.

chrome/browser/storage_monitor/volume_mount_watcher_win.cc

 // 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.
 
 #include "chrome/browser/storage_monitor/volume_mount_watcher_win.h"
 
 #include <windows.h>
 #include <dbt.h>
 #include <fileapi.h>
 
@@ skipping 355 matching lines @@
   }
 }
 
 void VolumeMountWatcherWin::SetNotifications(
     StorageMonitor::Receiver* notifications) {
   notifications_ = notifications;
 }
 
 VolumeMountWatcherWin::~VolumeMountWatcherWin() {
   weak_factory_.InvalidateWeakPtrs();
+  device_info_worker_pool_->Shutdown();
 }
 
 void VolumeMountWatcherWin::HandleDeviceAttachEventOnUIThread(
     const base::FilePath& device_path,
     const MountPointInfo& info) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
   device_metadata_[device_path.value()] = info;
 
   DeviceCheckComplete(device_path);
@@ skipping 21 matching lines @@
   // If the device isn't type removable (like a CD), it won't be there.
   if (device_info == device_metadata_.end())
     return;
 
   if (notifications_)
     notifications_->ProcessDetach(device_info->second.device_id);
   device_metadata_.erase(device_info);
 }
 
 }  // namespace chrome