Adds WmWindow and converts WindowState to use it

ash/wm/drag_details.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 ASH_WM_DRAG_DETAILS_H_
 #define ASH_WM_DRAG_DETAILS_H_
 
 #include "ash/ash_export.h"
 #include "ash/wm/wm_types.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/wm/public/window_move_client.h"
 
 namespace aura {
 class Window;
 }
 
 namespace ash {
 
 namespace wm {
+class WmWindow;
 class WindowState;
 }
 
 struct ASH_EXPORT DragDetails {
-  DragDetails(aura::Window* window,
+  DragDetails(wm::WmWindow* window,
               const gfx::Point& location,
               int window_component,
+              // TODO(sky): make wm type.
               aura::client::WindowMoveSource source);
   ~DragDetails();
 
   ash::wm::WindowStateType initial_state_type;
 
   // Initial bounds of the window in parent coordinates.
   const gfx::Rect initial_bounds_in_parent;
 
   // Restore bounds (in screen coordinates) of the window before the drag
   // started. Only set if the window is normal and is being dragged.
@@ skipping 23 matching lines @@
   // Source of the event initiating the drag.
   const aura::client::WindowMoveSource source;
 
   // True if the window should attach to the shelf after releasing.
   bool should_attach_to_shelf;
 };
 
 }  // namespace ash
 
 #endif  // ASH_WM_DRAG_DETAILS_H_