Create task_manager namespace and wrap classes related to TaskManager with it.

chrome/browser/task_manager/os_resource_win.h

 // 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.
 
-#ifndef CHROME_BROWSER_TASK_MANAGER_TASK_MANAGER_OS_RESOURCES_WIN_H_
-#define CHROME_BROWSER_TASK_MANAGER_TASK_MANAGER_OS_RESOURCES_WIN_H_
+#ifndef CHROME_BROWSER_TASK_MANAGER_OS_RESOURCE_WIN_H_
+#define CHROME_BROWSER_TASK_MANAGER_OS_RESOURCE_WIN_H_
 
 #include "base/process_util.h"
 
+namespace task_manager {
+
 // Get the current number of GDI handles in use (and peak on >= Win7+).
 void GetWinGDIHandles(base::ProcessHandle process,
                       size_t* current,
                       size_t* peak);
 
 // Get the current number of USER handles in use (and peak on >= Win7).
 void GetWinUSERHandles(base::ProcessHandle process,
                        size_t* current,
                        size_t* peak);
 
-#endif  // CHROME_BROWSER_TASK_MANAGER_TASK_MANAGER_OS_RESOURCES_WIN_H_
+}  // namespace task_manager
+
+#endif  // CHROME_BROWSER_TASK_MANAGER_OS_RESOURCE_WIN_H_