Make members of Singleton<T> private and only visible to the singleton type.

chrome_frame/external_tab.cc

 // Copyright (c) 2010 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.
 
 #include "chrome_frame/external_tab.h"
-#include "base/singleton.h"
+#include "base/lazy_instance.h"
 #include "base/tracked.h"
 #include "base/task.h"
 #include "base/waitable_event.h"
 #include "chrome/common/automation_messages.h"
 #include "chrome_frame/utils.h"
 
 DISABLE_RUNNABLE_METHOD_REFCOUNT(ExternalTabProxy);
 DISABLE_RUNNABLE_METHOD_REFCOUNT(UIDelegate);
 
 namespace {
-  Singleton<ChromeProxyFactory> g_proxy_factory;
+  static base::LazyInstance<ChromeProxyFactory> g_proxy_factory(
+      base::LINKER_INITIALIZED);
 
   struct UserDataHolder : public SyncMessageContext {
     explicit UserDataHolder(void* p) : data(p) {}
     void* data;
   };
 }
 
 
 ExternalTabProxy::ExternalTabProxy() : state_(NONE), tab_(0), tab_wnd_(NULL),
-    chrome_wnd_(NULL), proxy_factory_(g_proxy_factory.get()), proxy_(NULL),
+    chrome_wnd_(NULL), proxy_factory_(g_proxy_factory.Pointer()), proxy_(NULL),
     ui_delegate_(NULL) {
 }
 
 ExternalTabProxy::~ExternalTabProxy() {
   Destroy();
 }
 
 void ExternalTabProxy::Init() {
   if (m_hWnd == NULL) {
     // Create a window on the UI thread for marshaling messages back and forth
@@ skipping 293 matching lines @@
 }
 
 void ExternalTabProxy::TabClosed() {
   // TODO(stoyan):
 }
 
 void ExternalTabProxy::AttachTab(
     const IPC::AttachExternalTabParams& attach_params) {
   // TODO(stoyan):
 }