mash: Preliminary support for shelf auto-hide

ash/shelf/shelf_layout_manager_observer.h

 // Copyright 2013 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_SHELF_SHELF_LAYOUT_MANAGER_OBSERVER_H_
 #define ASH_SHELF_SHELF_LAYOUT_MANAGER_OBSERVER_H_
 
 #include "ash/ash_export.h"
 #include "ash/shelf/shelf_types.h"
 #include "ash/wm/common/background_animator.h"
 
 namespace aura {
 class Window;
 }
 
 namespace ash {
 
+class ShelfLayoutManager;
+
 class ASH_EXPORT ShelfLayoutManagerObserver {
  public:
   virtual ~ShelfLayoutManagerObserver() {}
 
   // Called when the target ShelfLayoutManager will be deleted.
   virtual void WillDeleteShelf() {}
 
   // Called when the visibility change is scheduled.
   virtual void WillChangeVisibilityState(ShelfVisibilityState new_state) {}
 
+  // Called when the visibility change is committed.
+  virtual void DidChangeVisibilityState(ShelfLayoutManager* layout_manager,

[msw, 2016/05/24 20:46:55]

optional nit: pass the ash::Shelf instead? ditto below.

[James Cook, 2016/05/25 00:25:43]

I moved this method to the delegate and removed the ShelfLayoutManager parameter
below.

+                                        ShelfVisibilityState new_state) {}
+
   // Called when the auto hide state is changed.
-  virtual void OnAutoHideStateChanged(ShelfAutoHideState new_state) {}
+  virtual void OnAutoHideStateChanged(ShelfLayoutManager* layout_manager,
+                                      ShelfAutoHideState new_state) {}
 
   // Called when shelf background animation is started.
   virtual void OnBackgroundUpdated(wm::ShelfBackgroundType background_type,
                                    BackgroundAnimatorChangeType change_type) {}
 };
 
 }  // namespace ash
 
 #endif  // ASH_SHELF_SHELF_LAYOUT_MANAGER_OBSERVER_H_