Delay wallpaper load by 2 * average wallpaper load time.

chrome/browser/ui/webui/chromeos/login/signin_screen_handler.cc

Index: chrome/browser/ui/webui/chromeos/login/signin_screen_handler.cc
diff --git a/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.cc b/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.cc
index 9a85f0a86ff62e4d7d46430e5866aa4d8c56766d..69bb9b3cfa3cb49943dba7fd520972a7167563bd 100644
--- a/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.cc
+++ b/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.cc
@@ -420,9 +420,12 @@ SigninScreenHandler::SigninScreenHandler(
   registrar_.Add(this,
                  chrome::NOTIFICATION_AUTH_CANCELLED,
                  content::NotificationService::AllSources());
+
+  WallpaperManager::Get()->AddObserver(this);
 }
 
 SigninScreenHandler::~SigninScreenHandler() {
+  WallpaperManager::Get()->RemoveObserver(this);
   weak_factory_.InvalidateWeakPtrs();
   SystemKeyEventListener* key_event_listener =
       SystemKeyEventListener::GetInstance();
@@ -1284,6 +1287,11 @@ void SigninScreenHandler::HandleLoadWallpaper(const std::string& email) {
     delegate_->LoadWallpaper(email);
 }
 
+void SigninScreenHandler::OnWallpaperAnimationFinished(
+    const std::string& email) {
+  CallJS("login.AccountPickerScreen.onWallpaperLoaded", email);
+}
+
 void SigninScreenHandler::HandleRebootSystem() {
   chromeos::DBusThreadManager::Get()->GetPowerManagerClient()->RequestRestart();
 }