Move Singleton and related structs to namespace base

ui/base/x/x11_foreign_window_manager.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 UI_BASE_X_X11_FOREIGN_WINDOW_MANAGER_H_
 #define UI_BASE_X_X11_FOREIGN_WINDOW_MANAGER_H_
 
 #include <map>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "ui/base/ui_base_export.h"
 #include "ui/gfx/x/x11_types.h"
 
 // A process wide singleton for selecting events on X windows which were not
 // created by Chrome.
+namespace base {
 template <typename T> struct DefaultSingletonTraits;
+}
 
 namespace ui {
 
 // Manages the events that Chrome has selected on X windows which were not
 // created by Chrome. This class allows several clients to select events
 // on the same X window.
 class UI_BASE_EXPORT XForeignWindowManager {
  public:
   static XForeignWindowManager* GetInstance();
 
   // Requests that events associated with |event_mask| on |xid| be reported to
   // Chrome. Returns an id to use for canceling the request.
   int RequestEvents(XID xid, long event_mask) WARN_UNUSED_RESULT;
 
   // Cancels the request with |request_id|. Unless there is another request for
   // events on the X window associated with |request_id|, this stops Chrome from
   // getting events for the X window.
   void CancelRequest(int request_id);
 
   // Called by X11DesktopHandler when |xid| is destroyed.
   void OnWindowDestroyed(XID xid);
 
  private:
-  friend struct DefaultSingletonTraits<XForeignWindowManager>;
+  friend struct base::DefaultSingletonTraits<XForeignWindowManager>;
 
   struct Request {
     Request(int request_id, long entry_event_mask);
     ~Request();
 
     int request_id;
     long event_mask;
   };
 
   XForeignWindowManager();
   ~XForeignWindowManager();
 
   // Updates which events are selected on |xid|.
   void UpdateSelectedEvents(XID xid);
 
   // The id of the next request.
   int next_request_id_;
 
   typedef std::vector<Request> RequestVector;
   std::map<XID, RequestVector> request_map_;
 
   DISALLOW_COPY_AND_ASSIGN(XForeignWindowManager);
 };
 
 }  // namespace ui
 
 #endif  // UI_BASE_X_X11_FOREIGN_WINDOW_MANAGER_H_