cros: Move LockWindow from chrome to ash

ash/login/ui/lock_window.h

 // Copyright 2014 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.
 
-#ifndef CHROME_BROWSER_CHROMEOS_LOGIN_UI_LOCK_WINDOW_H_
-#define CHROME_BROWSER_CHROMEOS_LOGIN_UI_LOCK_WINDOW_H_
+#ifndef ASH_LOGIN_UI_LOCK_WINDOW_H_
+#define ASH_LOGIN_UI_LOCK_WINDOW_H_
 
+#include "ash/ash_export.h"
 #include "base/macros.h"
 #include "ui/views/widget/widget.h"
 #include "ui/views/widget/widget_delegate.h"
 
 namespace views {
 class View;
 class Widget;
 }
 
-namespace chromeos {
+namespace ash {
 
 // Shows the widget for the lock screen.
-class LockWindow : public views::Widget, public views::WidgetDelegate {
+class ASH_EXPORT LockWindow : public views::Widget,
+                              public views::WidgetDelegate {
  public:
   LockWindow();
   ~LockWindow() override;
 
  private:
   // views::WidgetDelegate:
   views::View* GetInitiallyFocusedView() override;
   views::Widget* GetWidget() override;
   const views::Widget* GetWidget() const override;
 
   DISALLOW_COPY_AND_ASSIGN(LockWindow);
 };
 
-}  // namespace chromeos
+}  // namespace ash
 
-#endif  // CHROME_BROWSER_CHROMEOS_LOGIN_UI_LOCK_WINDOW_H_
+#endif  // ASH_LOGIN_UI_LOCK_WINDOW_H_