Move Singleton and related structs to namespace base

ppapi/proxy/plugin_var_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 PPAPI_PROXY_PLUGIN_VAR_TRACKER_H_
 #define PPAPI_PROXY_PLUGIN_VAR_TRACKER_H_
 
 #include <map>
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/shared_memory.h"
 #include "ppapi/c/pp_stdint.h"
 #include "ppapi/c/pp_var.h"
 #include "ppapi/proxy/ppapi_proxy_export.h"
 #include "ppapi/shared_impl/var_tracker.h"
 
+namespace base {
 template<typename T> struct DefaultSingletonTraits;
+}
+
 struct PPP_Class_Deprecated;
 
 namespace ppapi {
 
 class ProxyObjectVar;
 
 namespace proxy {
 
 class PluginDispatcher;
 
@@ skipping 68 matching lines @@
   int32 AddVarInternal(Var* var, AddVarRefMode mode) override;
   void TrackedObjectGettingOneRef(VarMap::const_iterator iter) override;
   void ObjectGettingZeroRef(VarMap::iterator iter) override;
   bool DeleteObjectInfoIfNecessary(VarMap::iterator iter) override;
   ArrayBufferVar* CreateArrayBuffer(uint32 size_in_bytes) override;
   ArrayBufferVar* CreateShmArrayBuffer(
       uint32 size_in_bytes,
       base::SharedMemoryHandle handle) override;
 
  private:
-  friend struct DefaultSingletonTraits<PluginVarTracker>;
+  friend struct base::DefaultSingletonTraits<PluginVarTracker>;
   friend class PluginProxyTestHarness;
 
   // Represents a var as received from the host.
   struct HostVar {
     HostVar(PluginDispatcher* d, int32 i);
 
     bool operator<(const HostVar& other) const;
 
     // The dispatcher that sent us this object. This is used so we know how to
     // send back requests on this object.
@@ skipping 81 matching lines @@
       UserDataToPluginImplementedVarMap;
   UserDataToPluginImplementedVarMap user_data_to_plugin_;
 
   DISALLOW_COPY_AND_ASSIGN(PluginVarTracker);
 };
 
 }  // namespace proxy
 }  // namespace ppapi
 
 #endif  // PPAPI_PROXY_PLUGIN_VAR_TRACKER_H_