Move Singleton and related structs to namespace base

chrome/browser/net/utility_process_mojo_proxy_resolver_factory.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 CHROME_BROWSER_NET_UTILITY_PROCESS_MOJO_PROXY_RESOLVER_FACTORY_H_
 #define CHROME_BROWSER_NET_UTILITY_PROCESS_MOJO_PROXY_RESOLVER_FACTORY_H_
 
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "base/threading/thread_checker.h"
 #include "base/timer/timer.h"
 #include "net/proxy/mojo_proxy_resolver_factory.h"
 
 namespace content {
 class UtilityProcessHost;
 }
-
+namespace base {
 template <typename Type>
 struct DefaultSingletonTraits;
+}  // namespace base
 
 // A factory used to create connections to Mojo proxy resolver services run in a
 // utility process. All Mojo proxy resolver services will be run in the same
 // utility process. Utility process crashes are detected and the utility
 // process is automatically restarted.
 class UtilityProcessMojoProxyResolverFactory
     : public net::MojoProxyResolverFactory {
  public:
   static UtilityProcessMojoProxyResolverFactory* GetInstance();
 
   // Overridden from net::MojoProxyResolverFactory:
   scoped_ptr<base::ScopedClosureRunner> CreateResolver(
       const mojo::String& pac_script,
       mojo::InterfaceRequest<net::interfaces::ProxyResolver> req,
       net::interfaces::ProxyResolverFactoryRequestClientPtr client) override;
 
  private:
-  friend struct DefaultSingletonTraits<UtilityProcessMojoProxyResolverFactory>;
+  friend struct base::DefaultSingletonTraits<
+      UtilityProcessMojoProxyResolverFactory>;
   UtilityProcessMojoProxyResolverFactory();
   ~UtilityProcessMojoProxyResolverFactory() override;
 
   // Error handler callback for |resolver_factory_|.
   void OnConnectionError();
 
   // Invoked each time a proxy resolver is destroyed.
   void OnResolverDestroyed();
 
   // Invoked once an idle timeout has elapsed after all proxy resolvers are
@@ skipping 10 matching lines @@
   size_t num_proxy_resolvers_ = 0;
 
   base::OneShotTimer<UtilityProcessMojoProxyResolverFactory> idle_timer_;
 
   base::ThreadChecker thread_checker_;
 
   DISALLOW_COPY_AND_ASSIGN(UtilityProcessMojoProxyResolverFactory);
 };
 
 #endif  // CHROME_BROWSER_NET_UTILITY_PROCESS_MOJO_PROXY_RESOLVER_FACTORY_H_