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

chrome/browser/chromeos/login/screen_locker.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/browser/chromeos/login/screen_locker.h"
 
 #include <gdk/gdkx.h>
 #include <string>
 #include <vector>
 #include <X11/extensions/XTest.h>
 #include <X11/keysym.h>
 // Evil hack to undo X11 evil #define. See crosbug.com/
 #undef Status
 
 #include "app/l10n_util.h"
 #include "app/resource_bundle.h"
 #include "app/x11_util.h"
 #include "base/command_line.h"
+#include "base/lazy_instance.h"
 #include "base/metrics/histogram.h"
 #include "base/message_loop.h"
-#include "base/singleton.h"
 #include "base/string_util.h"
 #include "base/timer.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/browser_list.h"
 #include "chrome/browser/browser_thread.h"
 #include "chrome/browser/browser_window.h"
 #include "chrome/browser/chromeos/cros/input_method_library.h"
 #include "chrome/browser/chromeos/cros/keyboard_library.h"
 #include "chrome/browser/chromeos/cros/login_library.h"
 #include "chrome/browser/chromeos/cros/screen_lock_library.h"
@@ skipping 155 matching lines @@
   }
 
   NotificationRegistrar registrar_;
   std::string saved_previous_input_method_id_;
   std::string saved_current_input_method_id_;
   std::vector<std::string> saved_active_input_method_list_;
 
   DISALLOW_COPY_AND_ASSIGN(ScreenLockObserver);
 };
 
+static base::LazyInstance<ScreenLockObserver> g_screen_lock_observer(
+    base::LINKER_INITIALIZED);
+
 // A ScreenLock window that covers entire screen to keep the keyboard
 // focus/events inside the grab widget.
 class LockWindow : public views::WidgetGtk {
  public:
   LockWindow()
       : views::WidgetGtk(views::WidgetGtk::TYPE_WINDOW),
         toplevel_focus_widget_(NULL) {
     EnableDoubleBuffer(true);
   }
 
@@ skipping 687 matching lines @@
     // This can happen when a user requested unlock, but PowerManager
     // rejected because the computer is closed, then PowerManager unlocked
     // because it's open again and the above failure message arrives.
     // This'd be extremely rare, but may still happen.
     VLOG(1) << "UnlockScreenFailed: screen is already unlocked.";
   }
 }
 
 // static
 void ScreenLocker::InitClass() {
-  Singleton<ScreenLockObserver>::get();
+  g_screen_lock_observer.Get();
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // ScreenLocker, private:
 
 ScreenLocker::~ScreenLocker() {
   DCHECK(MessageLoop::current()->type() == MessageLoop::TYPE_UI);
   ClearErrors();
   if (input_event_observer_.get())
     MessageLoopForUI::current()->RemoveObserver(input_event_observer_.get());
@@ skipping 122 matching lines @@
 
 bool ScreenLocker::AcceleratorPressed(const views::Accelerator& accelerator) {
   if (!background_view_->IsScreenSaverVisible()) {
     StartScreenSaver();
     return true;
   }
   return false;
 }
 
 }  // namespace chromeos