Add a new GetInstance() method for remaining files with singleton classes under chrome/browser.

chrome/browser/upgrade_detector.h

 // 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.
 
 #ifndef CHROME_BROWSER_UPGRADE_DETECTOR_H_
 #define CHROME_BROWSER_UPGRADE_DETECTOR_H_
 #pragma once
 
 #include "base/singleton.h"
 #include "base/timer.h"
 
 class PrefService;
 
 ///////////////////////////////////////////////////////////////////////////////
 // UpgradeDetector
 //
 // This class is a singleton class that monitors when an upgrade happens in the
 // background. We basically ask Omaha what it thinks the latest version is and
 // if our version is lower we send out a notification upon:
 //   a) Detecting an upgrade and...
 //   b) When we think the user should be notified about the upgrade.
 // The latter happens much later, since we don't want to be too annoying.
 //
 class UpgradeDetector {
  public:
+  // Returns the singleton instance.
+  static UpgradeDetector* GetInstance();
+
   ~UpgradeDetector();
 
   static void RegisterPrefs(PrefService* prefs);
 
   bool notify_upgrade() { return notify_upgrade_; }
 
  private:
+  friend struct DefaultSingletonTraits<UpgradeDetector>;
+
   UpgradeDetector();
-  friend struct DefaultSingletonTraits<UpgradeDetector>;
 
   // Launches a task on the file thread to check if we have the latest version.
   void CheckForUpgrade();
 
   // Sends out a notification and starts a one shot timer to wait until
   // notifying the user.
   void UpgradeDetected();
 
   // The function that sends out a notification (after a certain time has
   // elapsed) that lets the rest of the UI know we should start notifying the
@@ skipping 12 matching lines @@
   ScopedRunnableMethodFactory<UpgradeDetector> method_factory_;
 
   // Whether we have waited long enough after detecting an upgrade (to see
   // is we should start nagging about upgrading).
   bool notify_upgrade_;
 
   DISALLOW_COPY_AND_ASSIGN(UpgradeDetector);
 };
 
 #endif  // CHROME_BROWSER_UPGRADE_DETECTOR_H_