Fix crash/leak issue in native_view_host_gtk.cc.

views/widget/widget_gtk.cc

 // Copyright (c) 2009 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/widget/widget_gtk.h"
 
 #include "app/drag_drop_types.h"
 #include "app/gfx/path.h"
 #include "app/os_exchange_data.h"
 #include "app/os_exchange_data_provider_gtk.h"
@@ skipping 94 matching lines @@
     MessageLoopForUI* loop = MessageLoopForUI::current();
     if (loop)
       loop->AddObserver(DropObserver::Get());
   }
 
   if (type_ != TYPE_CHILD)
     focus_manager_.reset(new FocusManager(this));
 }
 
 WidgetGtk::~WidgetGtk() {
+  DCHECK(delete_on_destroy_ || widget_ == NULL);
   if (type_ != TYPE_CHILD)
     ActiveWindowWatcherX::RemoveObserver(this);
   MessageLoopForUI::current()->RemoveObserver(this);
 }
 
 GtkWindow* WidgetGtk::GetTransientParent() const {
   return (type_ != TYPE_CHILD && widget_) ?
       gtk_window_get_transient_for(GTK_WINDOW(widget_)) : NULL;
 }
 
@@ skipping 312 matching lines @@
   Hide();
   if (close_widget_factory_.empty()) {
     // And we delay the close just in case we're on the stack.
     MessageLoop::current()->PostTask(FROM_HERE,
         close_widget_factory_.NewRunnableMethod(
             &WidgetGtk::CloseNow));
   }
 }
 
 void WidgetGtk::CloseNow() {
-  if (widget_)
+  if (widget_) {
     gtk_widget_destroy(widget_);
+    widget_ = NULL;
+  }
 }
 
 void WidgetGtk::Show() {
   if (widget_)
     gtk_widget_show(widget_);
 }
 
 void WidgetGtk::Hide() {
   if (widget_)
     gtk_widget_hide(widget_);
@@ skipping 853 matching lines @@
 
 // static
 Widget* Widget::GetWidgetFromNativeWindow(gfx::NativeWindow native_window) {
   gpointer raw_widget = g_object_get_data(G_OBJECT(native_window), kWidgetKey);
   if (raw_widget)
     return reinterpret_cast<Widget*>(raw_widget);
   return NULL;
 }
 
 }  // namespace views