GTK: don't dereference stale ConstrainedWindow pointer.

chrome/browser/login_prompt_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 "chrome/browser/login_prompt.h"
 
 #include <gtk/gtk.h>
 
 #include "app/l10n_util.h"
 #include "chrome/browser/chrome_thread.h"
@@ skipping 164 matching lines @@
   }
 
   virtual void CancelAuth() {
     if (WasAuthHandled(true))
       return;
 
     ChromeThread::PostTask(
         ChromeThread::UI, FROM_HERE,
         NewRunnableMethod(this, &LoginHandlerGtk::CloseContentsDeferred));
     ChromeThread::PostTask(
-      ChromeThread::UI, FROM_HERE,
-      NewRunnableMethod(this, &LoginHandlerGtk::SendNotifications));
+        ChromeThread::UI, FROM_HERE,
+        NewRunnableMethod(this, &LoginHandlerGtk::SendNotifications));
     ChromeThread::PostTask(
         ChromeThread::IO, FROM_HERE,
         NewRunnableMethod(this, &LoginHandlerGtk::CancelAuthDeferred));
   }
 
   virtual void OnRequestCancelled() {
     DCHECK(ChromeThread::CurrentlyOn(ChromeThread::IO)) <<
         "Why is OnRequestCancelled called from the UI thread?";
 
     // Reference is no longer valid.
@@ skipping 11 matching lines @@
   virtual void DeleteDelegate() {
     if (!WasAuthHandled(true)) {
       ChromeThread::PostTask(
           ChromeThread::IO, FROM_HERE,
           NewRunnableMethod(this, &LoginHandlerGtk::CancelAuthDeferred));
       ChromeThread::PostTask(
           ChromeThread::UI, FROM_HERE,
           NewRunnableMethod(this, &LoginHandlerGtk::SendNotifications));
     }
 
+    // The constrained window is going to delete itself; clear our pointer.
+    dialog_ = NULL;
     SetModel(NULL);
 
     // Delete this object once all InvokeLaters have been called.
     ChromeThread::ReleaseSoon(ChromeThread::IO, FROM_HERE, this);
   }
 
  private:
   friend class LoginPrompt;
 
   // Calls SetAuth from the IO loop.
@@ skipping 114 matching lines @@
   // so it doesn't try and access this when its too late.
   LoginModel* login_model_;
 
   DISALLOW_COPY_AND_ASSIGN(LoginHandlerGtk);
 };
 
 // static
 LoginHandler* LoginHandler::Create(URLRequest* request) {
   return new LoginHandlerGtk(request);
 }