chromeos: Explicitly initialize and shut down UpgradeDetectorChromeos.

chrome/browser/chromeos/upgrade_detector_chromeos.cc

 // Copyright (c) 2011 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/upgrade_detector_chromeos.h"
 
 #include "base/memory/singleton.h"
 #include "chrome/browser/chromeos/cros/cros_library.h"
 
 namespace {
 
 // How long to wait (each cycle) before checking which severity level we should
 // be at. Once we reach the highest severity, the timer will stop.
 const int kNotifyCycleTimeMs = 20 * 60 * 1000;  // 20 minutes.
 
 }  // namespace
 
-UpgradeDetectorChromeos::UpgradeDetectorChromeos() {
-  if (chromeos::CrosLibrary::Get())
-    chromeos::CrosLibrary::Get()->GetUpdateLibrary()->AddObserver(this);
+UpgradeDetectorChromeos::UpgradeDetectorChromeos() : initialized_(false) {
 }
 
 UpgradeDetectorChromeos::~UpgradeDetectorChromeos() {
+}
+
+void UpgradeDetectorChromeos::Init() {
+  if (chromeos::CrosLibrary::Get())
+    chromeos::CrosLibrary::Get()->GetUpdateLibrary()->AddObserver(this);
+  initialized_ = true;
+}
+
+void UpgradeDetectorChromeos::Shutdown() {
+  // Init() may not be called from tests (ex. BrowserMainTest).
+  if (!initialized_)
+    return;
   if (chromeos::CrosLibrary::Get())
     chromeos::CrosLibrary::Get()->GetUpdateLibrary()->RemoveObserver(this);
 }
 
 void UpgradeDetectorChromeos::UpdateStatusChanged(
     const chromeos::UpdateLibrary::Status& status) {
   if (status.status != chromeos::UPDATE_STATUS_UPDATED_NEED_REBOOT)
     return;
 
   NotifyUpgradeDetected();
@@ skipping 37 matching lines @@
 
 // static
 UpgradeDetectorChromeos* UpgradeDetectorChromeos::GetInstance() {
   return Singleton<UpgradeDetectorChromeos>::get();
 }
 
 // static
 UpgradeDetector* UpgradeDetector::GetInstance() {
   return UpgradeDetectorChromeos::GetInstance();
 }