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

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

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/ui/webui/chromeos/login/oobe_ui.h"
 
 #include <string>
 
 #include "base/command_line.h"
 #include "base/logging.h"
@@ skipping 225 matching lines @@
   // Note, handlers_[0] is a GenericHandler used by the WebUI.
   for (size_t i = 0; i < handlers_.size(); ++i)
     handlers_[i]->GetLocalizedStrings(localized_strings);
   ChromeURLDataManager::DataSource::SetFontAndTextDirection(localized_strings);
 
   if (!CommandLine::ForCurrentProcess()->HasSwitch(switches::kDisableNewOobe))
     localized_strings->SetString("oobeType", "new");
   else
     localized_strings->SetString("oobeType", "old");
 
+  // If we're not doing boot animation then WebUI should trigger
+  // wallpaper load on boot.
+  if (CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kDisableBootAnimation)) {
+    localized_strings->SetString("bootIntoWallpaper", "on");
+  } else {
+    localized_strings->SetString("bootIntoWallpaper", "off");
+  }
+
   // OobeUI is used for OOBE/login and lock screen.
   if (BaseLoginDisplayHost::default_host())
     localized_strings->SetString("screenType", "login");
   else
     localized_strings->SetString("screenType", "lock");
 }
 
 void OobeUI::AddScreenHandler(BaseScreenHandler* handler) {
   web_ui()->AddMessageHandler(handler);
   handlers_.push_back(handler);
@@ skipping 15 matching lines @@
 
 void OobeUI::ResetSigninScreenHandlerDelegate() {
   signin_screen_handler_->SetDelegate(NULL);
 }
 
 void OobeUI::OnLoginPromptVisible() {
   user_image_screen_actor_->CheckCameraPresence();
 }
 
 }  // namespace chromeos