Add simplistic screenlock application.

mash/wm/window_manager_application.h

Index: mash/wm/window_manager_application.h
diff --git a/mash/wm/window_manager_application.h b/mash/wm/window_manager_application.h
index cf0f26c0f043ff759a0806b7d6e0ab38b2bf63d4..0f06e73a9e4b51baa2912d4c4d9a1a96885cc0b5 100644
--- a/mash/wm/window_manager_application.h
+++ b/mash/wm/window_manager_application.h
@@ -39,6 +39,7 @@ namespace wm {
 
 class AcceleratorRegistrarImpl;
 class BackgroundLayout;
+class ScreenlockLayout;
 class ShadowController;
 class ShelfLayout;
 class UserWindowControllerImpl;
@@ -140,6 +141,7 @@ class WindowManagerApplication
       user_window_controller_requests_;
 
   scoped_ptr<BackgroundLayout> background_layout_;
+  scoped_ptr<ScreenlockLayout> screenlock_layout_;
   scoped_ptr<ShelfLayout> shelf_layout_;
   scoped_ptr<WindowLayout> window_layout_;