Make login code not depend on Ash when use_athena=1

chrome/browser/chromeos/login/supervised/supervised_user_creation_screen.cc

Index: chrome/browser/chromeos/login/supervised/supervised_user_creation_screen.cc
diff --git a/chrome/browser/chromeos/login/supervised/supervised_user_creation_screen.cc b/chrome/browser/chromeos/login/supervised/supervised_user_creation_screen.cc
index 35bc61e951e6c0a2bb1ec2bf24d26025f34df7f2..514f2f2b6fe8847383acfdd56071bc7a27fcfac5 100644
--- a/chrome/browser/chromeos/login/supervised/supervised_user_creation_screen.cc
+++ b/chrome/browser/chromeos/login/supervised/supervised_user_creation_screen.cc
@@ -4,8 +4,6 @@
 
 #include "chrome/browser/chromeos/login/supervised/supervised_user_creation_screen.h"
 
-#include "ash/desktop_background/desktop_background_controller.h"
-#include "ash/shell.h"
 #include "base/rand_util.h"
 #include "base/values.h"
 #include "chrome/browser/chromeos/camera_detector.h"
@@ -39,6 +37,11 @@
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/gfx/image/image_skia.h"
 
+#if !defined(USE_ATHENA)
+#include "ash/desktop_background/desktop_background_controller.h"
+#include "ash/shell.h"
+#endif
+
 namespace chromeos {
 
 namespace {
@@ -359,8 +362,10 @@ void SupervisedUserCreationScreen::OnManagerFullyAuthenticated(
   DCHECK(controller_.get());
   // For manager user, move desktop to locked container so that windows created
   // during the user image picker step are below it.
+#if !defined(USE_ATHENA)
   ash::Shell::GetInstance()->
       desktop_background_controller()->MoveDesktopToLockedContainer();
+#endif
 
   controller_->SetManagerProfile(manager_profile);
   if (actor_)