ash: Fix event processing in modal windows in login/lock screen.

ash/root_window_controller.h

 // 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.
 
 #ifndef ASH_ROOT_WINDOW_CONTROLLER_H_
 #define ASH_ROOT_WINDOW_CONTROLLER_H_
 
 #include "ash/ash_export.h"
 #include "base/basictypes.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 39 matching lines @@
   }
 
   WorkspaceController* workspace_controller() {
     return workspace_controller_.get();
   }
 
   ScreenDimmer* screen_dimmer() {
     return screen_dimmer_.get();
   }
 
-  SystemModalContainerLayoutManager* GetSystemModalLayoutManager();
+  // Returns the layout-manager for the appropriate modal-container. If the
+  // window is inside the lockscreen modal container, then the layout manager
+  // for that is returned. Otherwise the layout manager for the default modal
+  // container is returned.
+  // If no window is specified (i.e. |window| is NULL), then the lockscreen
+  // modal container is used if the screen is currently locked. Otherwise, the
+  // default modal container is used.
+  SystemModalContainerLayoutManager* GetSystemModalLayoutManager(
+      aura::Window* window);
 
   aura::Window* GetContainer(int container_id);
 
   void InitLayoutManagers();
   void CreateContainers();
 
   // Initializes |background_|.  |is_first_run_after_boot| determines the
   // background's initial color.
   void CreateSystemBackground(bool is_first_run_after_boot);
 
@@ skipping 38 matching lines @@
   scoped_ptr<ToplevelWindowEventHandler> modal_container_handler_;
   scoped_ptr<ToplevelWindowEventHandler> lock_modal_container_handler_;
 
   DISALLOW_COPY_AND_ASSIGN(RootWindowController);
 };
 
 }  // namespace internal
 }  // ash
 
 #endif  //  ASH_ROOT_WINDOW_CONTROLLER_H_