Add TestBrowserThreadBundle into RenderViewHostTestHarness. Kill some unnecessary real threads.

chrome/browser/storage_monitor/volume_mount_watcher_win.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_STORAGE_MONITOR_VOLUME_MOUNT_WATCHER_WIN_H_
 #define CHROME_BROWSER_STORAGE_MONITOR_VOLUME_MOUNT_WATCHER_WIN_H_
 
 #include <map>
 #include <set>
 #include <string>
@@ skipping 82 matching lines @@
   // devices freeze workers trying to get device info, resulting in
   // shutdown hangs.
   scoped_refptr<base::SequencedWorkerPool> device_info_worker_pool_;
   scoped_refptr<base::SequencedTaskRunner> task_runner_;
 
  private:
   friend class test::TestVolumeMountWatcherWin;
 
   // Key: Mass storage device mount point.
   // Value: Mass storage device metadata.
-  typedef std::map<base::string16, StorageInfo> MountPointDeviceMetadataMap;
+  typedef std::map<base::FilePath, StorageInfo> MountPointDeviceMetadataMap;
 
   // Maintain a set of device attribute check calls in-flight. Only accessed
   // on the UI thread. This is to try and prevent the same device from
   // occupying our worker pool in case of windows API call hangs.
   std::set<base::FilePath> pending_device_checks_;
 
   // A map from device mount point to device metadata. Only accessed on the UI
   // thread.
   MountPointDeviceMetadataMap device_metadata_;
 
   base::WeakPtrFactory<VolumeMountWatcherWin> weak_factory_;
 
   // The notifications object to use to signal newly attached volumes. Only
   // removable devices will be notified.
   StorageMonitor::Receiver* notifications_;
 
   DISALLOW_COPY_AND_ASSIGN(VolumeMountWatcherWin);
 };
 
 }  // namespace chrome
 
 #endif  // CHROME_BROWSER_STORAGE_MONITOR_VOLUME_MOUNT_WATCHER_WIN_H_