This CL replaces e-mail with AccountId in wallpaper manager code.

chrome/browser/chromeos/login/ui/webui_login_display.cc

Index: chrome/browser/chromeos/login/ui/webui_login_display.cc
diff --git a/chrome/browser/chromeos/login/ui/webui_login_display.cc b/chrome/browser/chromeos/login/ui/webui_login_display.cc
index 36ca55a85ac38f8875e861efc1f63a9fef71ca82..f6fab4e420c412280811131df19fdb2c4780580f 100644
--- a/chrome/browser/chromeos/login/ui/webui_login_display.cc
+++ b/chrome/browser/chromeos/login/ui/webui_login_display.cc
@@ -232,13 +232,12 @@ void WebUILoginDisplay::MigrateUserData(const std::string& old_password) {
     delegate_->MigrateUserData(old_password);
 }
 
-void WebUILoginDisplay::LoadWallpaper(const std::string& username) {
-  WallpaperManager::Get()->SetUserWallpaperDelayed(username);
+void WebUILoginDisplay::LoadWallpaper(const AccountId& account_id) {
+  WallpaperManager::Get()->SetUserWallpaperDelayed(account_id);
 }
 
 void WebUILoginDisplay::LoadSigninWallpaper() {
-  WallpaperManager::Get()->SetDefaultWallpaperDelayed(
-      login::SignInAccountId().GetUserEmail());
+  WallpaperManager::Get()->SetDefaultWallpaperDelayed(login::SignInAccountId());
 }
 
 void WebUILoginDisplay::OnSigninScreenReady() {