Add virtualKeyboardPrivate.onKeyboardClosed API.

ash/common/wm/workspace/workspace_layout_manager.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_COMMON_WM_WORKSPACE_WORKSPACE_LAYOUT_MANAGER_H_
 #define ASH_COMMON_WM_WORKSPACE_WORKSPACE_LAYOUT_MANAGER_H_
 
 #include <memory>
 #include <set>
 
@@ skipping 67 matching lines @@
   void OnWindowBoundsChanged(WmWindow* window,
                              const gfx::Rect& old_bounds,
                              const gfx::Rect& new_bounds) override;
 
   // WmActivationObserver overrides:
   void OnWindowActivated(WmWindow* gained_active,
                          WmWindow* lost_active) override;
 
   // keyboard::KeyboardControllerObserver overrides:
   void OnKeyboardBoundsChanging(const gfx::Rect& new_bounds) override;
+  void OnKeyboardClosed() override {}
 
   // WindowStateObserver overrides:
   void OnPostWindowStateTypeChange(wm::WindowState* window_state,
                                    wm::WindowStateType old_type) override;
 
   // ShellObserver overrides:
   void OnFullscreenStateChanged(bool is_fullscreen, WmWindow* root) override {
     // Do nothing. Fullscreen state change is observed by the
     // WmRootWindowControllerObserver::OnFullscreenStateChanged().
     // Because the name is conflicting, some compiler warns because this is
@@ skipping 43 matching lines @@
   // A window which covers the full container and which gets inserted behind the
   // topmost visible window.
   std::unique_ptr<WorkspaceLayoutManagerBackdropDelegate> backdrop_delegate_;
 
   DISALLOW_COPY_AND_ASSIGN(WorkspaceLayoutManager);
 };
 
 }  // namespace ash
 
 #endif  // ASH_COMMON_WM_WORKSPACE_WORKSPACE_LAYOUT_MANAGER_H_