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

chrome/browser/ui/webui/options/browser_options_handler.cc

Index: chrome/browser/ui/webui/options/browser_options_handler.cc
diff --git a/chrome/browser/ui/webui/options/browser_options_handler.cc b/chrome/browser/ui/webui/options/browser_options_handler.cc
index 68df1d0e137e7096512ce6348e1254dc52ff2062..45196da88100becac29587ff114ccc5b962b5ed6 100644
--- a/chrome/browser/ui/webui/options/browser_options_handler.cc
+++ b/chrome/browser/ui/webui/options/browser_options_handler.cc
@@ -547,7 +547,7 @@ void BrowserOptionsHandler::GetLocalizedValues(base::DictionaryValue* values) {
     const user_manager::User* user =
         chromeos::ProfileHelper::Get()->GetUserByProfile(profile);
     if (user && (user->GetType() != user_manager::USER_TYPE_GUEST))
-      username = user->email();
+      username = user->GetUserID().GetUserEmail();
   }
   if (!username.empty())
     username = gaia::SanitizeEmail(gaia::CanonicalizeEmail(username));
@@ -1031,7 +1031,7 @@ void BrowserOptionsHandler::InitializePage() {
 
   OnWallpaperManagedChanged(
       chromeos::WallpaperManager::Get()->IsPolicyControlled(
-          user_manager::UserManager::Get()->GetActiveUser()->email()));
+          user_manager::UserManager::Get()->GetActiveUser()->GetUserID()));
 
   policy::ConsumerManagementService* consumer_management =
       g_browser_process->platform_part()->browser_policy_connector_chromeos()->
@@ -1443,7 +1443,7 @@ void BrowserOptionsHandler::ThemesSetNative(const base::ListValue* args) {
 #if defined(OS_CHROMEOS)
 void BrowserOptionsHandler::UpdateAccountPicture() {
   std::string email =
-      user_manager::UserManager::Get()->GetLoggedInUser()->email();
+      user_manager::UserManager::Get()->GetLoggedInUser()->GetUserID().GetUserEmail();
   if (!email.empty()) {
     web_ui()->CallJavascriptFunction("BrowserOptions.updateAccountPicture");
     base::StringValue email_value(email);