Enable wallpaper boot animation for boot into sign in too. Add flag to disable it.

chrome/browser/chromeos/system/ash_system_tray_delegate.cc

Index: chrome/browser/chromeos/system/ash_system_tray_delegate.cc
diff --git a/chrome/browser/chromeos/system/ash_system_tray_delegate.cc b/chrome/browser/chromeos/system/ash_system_tray_delegate.cc
index 2756b2ac20adb66f66da9dac513d5126ec2636e6..1facfa46eceea9bc27e232d66ff05d3389eb93dd 100644
--- a/chrome/browser/chromeos/system/ash_system_tray_delegate.cc
+++ b/chrome/browser/chromeos/system/ash_system_tray_delegate.cc
@@ -47,7 +47,6 @@
 #include "chrome/browser/chromeos/login/message_bubble.h"
 #include "chrome/browser/chromeos/login/user.h"
 #include "chrome/browser/chromeos/login/user_manager.h"
-#include "chrome/browser/chromeos/login/wizard_controller.h"
 #include "chrome/browser/chromeos/mobile_config.h"
 #include "chrome/browser/chromeos/status/data_promo_notification.h"
 #include "chrome/browser/chromeos/status/network_menu.h"
@@ -256,14 +255,8 @@ class SystemTrayDelegate : public ash::SystemTrayDelegate,
 
   // Overridden from ash::SystemTrayDelegate:
   virtual bool GetTrayVisibilityOnStartup() OVERRIDE {
-    // If we're either logged in (doesn't matter in KioskMode or not),
-    // or not in KioskMode at all, return true.
-    // If not registered i.e. OOBE is still active, start with tray hidden,
-    // it will be enabled if needed by OOBE flow.
-    bool is_registered = chromeos::WizardController::IsDeviceRegistered();
-    return UserManager::Get()->IsUserLoggedIn() ||
-        (!chromeos::KioskModeSettings::Get()->IsKioskModeEnabled() &&
-            is_registered);
+    // In case of OOBE / sign in screen tray will be shown later.
+    return UserManager::Get()->IsUserLoggedIn();
   }
 
   virtual const string16 GetUserDisplayName() const OVERRIDE {