Add virtualKeyboardPrivate.onKeyboardClosed API.

ash/app_list/app_list_presenter_delegate.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_APP_LIST_APP_LIST_PRESENTER_DELEGATE_H_
 #define ASH_APP_LIST_APP_LIST_PRESENTER_DELEGATE_H_
 
 #include <stdint.h>
 
 #include "ash/ash_export.h"
@@ skipping 52 matching lines @@
 
  private:
   void ProcessLocatedEvent(ui::LocatedEvent* event);
 
   // ui::EventHandler overrides:
   void OnMouseEvent(ui::MouseEvent* event) override;
   void OnGestureEvent(ui::GestureEvent* event) override;
 
   // KeyboardControllerObserver overrides:
   void OnKeyboardBoundsChanging(const gfx::Rect& new_bounds) override;
+  void OnKeyboardClosed() override {}
 
   // ShellObserver overrides:
   void OnShelfAlignmentChanged(WmWindow* root_window) override;
   void OnMaximizeModeStarted() override;
   void OnMaximizeModeEnded() override;
 
   // ShelfIconObserver overrides:
   void OnShelfIconPositionsChanged() override;
 
   // Whether the app list is visible (or in the process of being shown).
@@ skipping 10 matching lines @@
 
   // Owned by its widget.
   app_list::AppListView* view_ = nullptr;
 
   DISALLOW_COPY_AND_ASSIGN(AppListPresenterDelegate);
 };
 
 }  // namespace ash
 
 #endif  // ASH_APP_LIST_APP_LIST_PRESENTER_DELEGATE_H_