We should use UserID object to identify users instead of username.

chrome/browser/chromeos/preferences.cc

Index: chrome/browser/chromeos/preferences.cc
diff --git a/chrome/browser/chromeos/preferences.cc b/chrome/browser/chromeos/preferences.cc
index 26bdbd9ffae1e246efbaa0b6e0a0dabc93a509dc..ed196e2087881cfc4165741f940d50f69cdd1426 100644
--- a/chrome/browser/chromeos/preferences.cc
+++ b/chrome/browser/chromeos/preferences.cc
@@ -391,7 +391,7 @@ void Preferences::ApplyPreferences(ApplyReason reason,
                                    const std::string& pref_name) {
   DCHECK(reason != REASON_PREF_CHANGED || !pref_name.empty());
   const bool user_is_owner =
-      user_manager::UserManager::Get()->GetOwnerEmail() == user_->email();
+      user_manager::UserManager::Get()->GetOwnerID() == user_->GetUserID();
   const bool user_is_active = user_->is_active();
 
   system::TouchpadSettings touchpad_settings;