add HideAndClose in preference to having Close sometimes magically defer

ui/views/widget/desktop_aura/desktop_root_window_host_x11.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 UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_ROOT_WINDOW_HOST_X11_H_
 #define UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_ROOT_WINDOW_HOST_X11_H_
 
 #include <X11/Xlib.h>
 
 // Get rid of a macro from Xlib.h that conflicts with Aura's RootWindow class.
@@ skipping 75 matching lines @@
 
   // Dispatches a mouse event, taking mouse capture into account. If a
   // different host has capture, we translate the event to its coordinate space
   // and dispatch it to that host instead.
   void DispatchMouseEvent(ui::MouseEvent* event);
 
   // Overridden from DesktopRootWindowHost:
   virtual aura::RootWindow* Init(aura::Window* content_window,
                                  const Widget::InitParams& params) OVERRIDE;
   virtual void InitFocus(aura::Window* window) OVERRIDE;
+  virtual bool SetCloseOnHideCompletion() OVERRIDE;
   virtual void Close() OVERRIDE;
   virtual void CloseNow() OVERRIDE;
   virtual aura::RootWindowHost* AsRootWindowHost() OVERRIDE;
   virtual void ShowWindowWithState(ui::WindowShowState show_state) OVERRIDE;
   virtual void ShowMaximizedWithBounds(
       const gfx::Rect& restored_bounds) OVERRIDE;
   virtual bool IsVisible() const OVERRIDE;
   virtual void SetSize(const gfx::Size& size) OVERRIDE;
   virtual void CenterWindow(const gfx::Size& size) OVERRIDE;
   virtual void GetWindowPlacement(
@@ skipping 124 matching lines @@
   // can notify widgets when they have lost capture, which controls a bunch of
   // things in views like hiding menus.
   static DesktopRootWindowHostX11* g_current_capture;
 
   DISALLOW_COPY_AND_ASSIGN(DesktopRootWindowHostX11);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_ROOT_WINDOW_HOST_X11_H_