Move Singleton and related structs to namespace base

content/browser/browser_io_surface_manager_mac.h

 // Copyright 2015 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_BROWSER_IO_SURFACE_MANAGER_MAC_H_
 #define CONTENT_BROWSER_BROWSER_IO_SURFACE_MANAGER_MAC_H_
 
 #include <mach/mach.h>
 
 #include <map>
@@ skipping 48 matching lines @@
 
   // Generate a unique unguessable token that the child process associated
   // |child_process_id| can use to acquire IOSurface references.
   IOSurfaceManagerToken GenerateChildProcessToken(int child_process_id);
 
   // Invalidate a previously generated child process token.
   void InvalidateChildProcessToken(const IOSurfaceManagerToken& token);
 
  private:
   friend class BrowserIOSurfaceManagerTest;
-  friend struct DefaultSingletonTraits<BrowserIOSurfaceManager>;
+  friend struct base::DefaultSingletonTraits<BrowserIOSurfaceManager>;
 
   BrowserIOSurfaceManager();
   ~BrowserIOSurfaceManager() override;
 
   // Performs any initialization work.
   bool Initialize();
 
   // Message handler that is invoked on |dispatch_source_| when an
   // incoming message needs to be received.
   void HandleRequest();
@@ skipping 36 matching lines @@
   // Mutex that guards |initialized_|, |io_surfaces_|, |child_process_ids_|
   // and |gpu_process_token_|.
   base::Lock lock_;
 
   DISALLOW_COPY_AND_ASSIGN(BrowserIOSurfaceManager);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_BROWSER_IO_SURFACE_MANAGER_MAC_H_