Make Combobox portable

views/controls/native/native_view_host_win.cc

 // Copyright (c) 2006-2008 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.
 
 #include "views/controls/native/native_view_host_win.h"
 
 #include "app/gfx/canvas.h"
 #include "base/logging.h"
 #include "views/controls/native/native_view_host.h"
 #include "views/focus/focus_manager.h"
@@ skipping 33 matching lines @@
   FocusManager::InstallFocusSubclass(host_->native_view(), focus_view);
 }
 
 void NativeViewHostWin::NativeViewDetaching() {
   DCHECK(host_->native_view());
   FocusManager::UninstallFocusSubclass(host_->native_view());
   installed_clip_ = false;
 }
 
 void NativeViewHostWin::AddedToWidget() {
+  if (!IsWindow(host_->native_view()))
+    return;
   HWND parent_hwnd = GetParent(host_->native_view());
   HWND widget_hwnd = host_->GetWidget()->GetNativeView();
   if (parent_hwnd != widget_hwnd)
     SetParent(host_->native_view(), widget_hwnd);
   if (host_->IsVisibleInRootView())
     ShowWindow(host_->native_view(), SW_SHOW);
   else
     ShowWindow(host_->native_view(), SW_HIDE);
   host_->Layout();
 }
 
 void NativeViewHostWin::RemovedFromWidget() {
+  if (!IsWindow(host_->native_view()))
+    return;
   ShowWindow(host_->native_view(), SW_HIDE);
   SetParent(host_->native_view(), NULL);
 }
 
 void NativeViewHostWin::InstallClip(int x, int y, int w, int h) {
   HRGN clip_region = CreateRectRgn(x, y, x + w, y + h);
   // NOTE: SetWindowRgn owns the region (as well as the deleting the
   // current region), as such we don't delete the old region.
   SetWindowRgn(host_->native_view(), clip_region, FALSE);
   installed_clip_ = true;
@@ skipping 50 matching lines @@
 ////////////////////////////////////////////////////////////////////////////////
 // NativeViewHostWrapper, public:
 
 // static
 NativeViewHostWrapper* NativeViewHostWrapper::CreateWrapper(
     NativeViewHost* host) {
   return new NativeViewHostWin(host);
 }
 
 }  // namespace views