Remove NOTIFICATION_SYSTEM_SETTING_CHANGED, switch CrosSettings to base::CallbackRegistry.

chrome/browser/chromeos/login/version_info_updater.cc

Index: chrome/browser/chromeos/login/version_info_updater.cc
diff --git a/chrome/browser/chromeos/login/version_info_updater.cc b/chrome/browser/chromeos/login/version_info_updater.cc
index 84ff2ce3dba8f6e4ef39829ce28d6d30e1644118..6b51e5f2a8d65ced569616a1ea19d7ce6d7e7cb5 100644
--- a/chrome/browser/chromeos/login/version_info_updater.cc
+++ b/chrome/browser/chromeos/login/version_info_updater.cc
@@ -13,7 +13,6 @@
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/browser_process.h"
-#include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/chromeos/policy/device_cloud_policy_manager_chromeos.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/cros_settings_names.h"
@@ -53,9 +52,6 @@ VersionInfoUpdater::~VersionInfoUpdater() {
           GetDeviceCloudPolicyManager();
   if (policy_manager)
     policy_manager->core()->store()->RemoveObserver(this);
-
-  for (unsigned int i = 0; i < arraysize(kReportingFlags); ++i)
-    cros_settings_->RemoveSettingsObserver(kReportingFlags[i], this);
 }
 
 void VersionInfoUpdater::StartUpdate(bool is_official_build) {
@@ -82,8 +78,14 @@ void VersionInfoUpdater::StartUpdate(bool is_official_build) {
   }
 
   // Watch for changes to the reporting flags.
-  for (unsigned int i = 0; i < arraysize(kReportingFlags); ++i)
-    cros_settings_->AddSettingsObserver(kReportingFlags[i], this);
+  base::Closure callback =
+      base::Bind(&VersionInfoUpdater::UpdateEnterpriseInfo,
+                 base::Unretained(this));
+  for (unsigned int i = 0; i < arraysize(kReportingFlags); ++i) {
+    subscriptions_.push_back(
+        cros_settings_->AddSettingsObserver(kReportingFlags[i],
+                                            callback).release());
+  }
 }
 
 void VersionInfoUpdater::UpdateVersionLabel() {
@@ -134,14 +136,4 @@ void VersionInfoUpdater::OnStoreError(policy::CloudPolicyStore* store) {
   UpdateEnterpriseInfo();
 }
 
-void VersionInfoUpdater::Observe(
-    int type,
-    const content::NotificationSource& source,
-    const content::NotificationDetails& details) {
-  if (type == chrome::NOTIFICATION_SYSTEM_SETTING_CHANGED)
-    UpdateEnterpriseInfo();
-  else
-    NOTREACHED();
-}
-
 }  // namespace chromeos