x11: Reset the window handle after destroying it

ui/gl/gl_surface_glx.cc

 // 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.
 
 extern "C" {
 #include <X11/Xlib.h>
 }
 
 #include "ui/gl/gl_surface_glx.h"
 
@@ skipping 448 matching lines @@
   return true;
 }
 
 void NativeViewGLSurfaceGLX::Destroy() {
   if (window_) {
     ui::PlatformEventSource* event_source =
         ui::PlatformEventSource::GetInstance();
     if (event_source)
       event_source->RemovePlatformEventDispatcher(this);
     XDestroyWindow(g_display, window_);
+    window_ = 0;
     XFlush(g_display);
   }
 }
 
 bool NativeViewGLSurfaceGLX::CanDispatchEvent(const ui::PlatformEvent& event) {
   return event->type == Expose && event->xexpose.window == window_;
 }
 
 uint32_t NativeViewGLSurfaceGLX::DispatchEvent(const ui::PlatformEvent& event) {
   XEvent forwarded_event = *event;
@@ skipping 195 matching lines @@
 
 void* PbufferGLSurfaceGLX::GetConfig() {
   return config_;
 }
 
 PbufferGLSurfaceGLX::~PbufferGLSurfaceGLX() {
   Destroy();
 }
 
 }  // namespace gfx