[cros] Add support for transparent background in sign in screen.

chrome/browser/chromeos/login/webui_login_display_host.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/chromeos/login/webui_login_display_host.h"
 
 #include "ash/shell.h"
 #include "ash/shell_window_ids.h"
 #include "ash/wm/window_animations.h"
 #include "base/command_line.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/time.h"
 #include "chrome/browser/chromeos/kiosk_mode/kiosk_mode_settings.h"
 #include "chrome/browser/chromeos/login/oobe_display.h"
 #include "chrome/browser/chromeos/login/webui_login_display.h"
 #include "chrome/browser/chromeos/login/webui_login_view.h"
 #include "chrome/browser/chromeos/login/wizard_controller.h"
 #include "chrome/browser/ui/webui/chromeos/login/oobe_ui.h"
+#include "chrome/common/chrome_switches.h"
 #include "content/public/browser/web_ui.h"
 #include "ui/aura/window.h"
 #include "ui/views/widget/widget.h"
 
 namespace chromeos {
 
 namespace {
 
 // URL which corresponds to the login WebUI.
 const char kLoginURL[] = "chrome://oobe/login";
@@ skipping 113 matching lines @@
     login_view_ = NULL;
   }
 }
 
 void WebUILoginDisplayHost::LoadURL(const GURL& url) {
   if (!login_window_) {
     views::Widget::InitParams params(
         views::Widget::InitParams::TYPE_WINDOW_FRAMELESS);
     params.bounds = background_bounds();
     params.show_state = ui::SHOW_STATE_FULLSCREEN;
+    if (CommandLine::ForCurrentProcess()->HasSwitch(switches::kEnableNewOobe))
+      params.transparent = true;
     params.parent =
         ash::Shell::GetInstance()->GetContainer(
             ash::internal::kShellWindowId_LockScreenContainer);
 
     login_window_ = new views::Widget;
     login_window_->Init(params);
     login_view_ = new WebUILoginView();
 
     login_view_->Init(login_window_);
 
@@ skipping 18 matching lines @@
   return static_cast<OobeUI*>(login_view_->GetWebUI()->GetController());
 }
 
 WizardController* WebUILoginDisplayHost::CreateWizardController() {
   // TODO(altimofeev): ensure that WebUI is ready.
   OobeDisplay* oobe_display = GetOobeUI();
   return new WizardController(this, oobe_display);
 }
 
 }  // namespace chromeos