Move Singleton and related structs to namespace base

content/browser/gpu/gpu_surface_tracker.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 CONTENT_BROWSER_GPU_GPU_SURFACE_TRACKER_H_
 #define CONTENT_BROWSER_GPU_GPU_SURFACE_TRACKER_H_
 
 #include <map>
 
 #include "base/basictypes.h"
@@ skipping 103 matching lines @@
                 const scoped_refptr<SurfaceRef>& surface_ref);
     ~SurfaceInfo();
     int renderer_id;
     int render_widget_id;
     gfx::AcceleratedWidget native_widget;
     gfx::GLSurfaceHandle handle;
     scoped_refptr<SurfaceRef> surface_ref;
   };
   typedef std::map<int, SurfaceInfo> SurfaceMap;
 
-  friend struct DefaultSingletonTraits<GpuSurfaceTracker>;
+  friend struct base::DefaultSingletonTraits<GpuSurfaceTracker>;
 
   GpuSurfaceTracker();
   ~GpuSurfaceTracker() override;
 
   base::Lock lock_;
   SurfaceMap surface_map_;
   int next_surface_id_;
 
   DISALLOW_COPY_AND_ASSIGN(GpuSurfaceTracker);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_GPU_GPU_SURFACE_TRACKER_H_