Handle resubmission of HTTP Posts.

content/browser/web_contents/navigation_controller_impl.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.
 
 #include "content/browser/web_contents/navigation_controller_impl.h"
 
 #include "base/bind.h"
 #include "base/file_util.h"
 #include "base/logging.h"
 #include "base/string_number_conversions.h"  // Temporary
@@ skipping 292 matching lines @@
   // CanReload method.
   if (current_index == -1) {
     return;
   }
 
   if (g_check_for_repost && check_for_repost &&
       GetEntryAtIndex(current_index)->GetHasPostData()) {
     // The user is asking to reload a page with POST data. Prompt to make sure
     // they really want to do this. If they do, the dialog will call us back
     // with check_for_repost = false.
-    content::NotificationService::current()->Notify(
-        content::NOTIFICATION_REPOST_WARNING_SHOWN,
-        content::Source<NavigationController>(this),
-        content::NotificationService::NoDetails());
-
+    if (content::NotificationService::current()) {
+      // TODO(sgurun): What is the proper way to handle this? create in
+      // contentviewcore?
+      content::NotificationService::current()->Notify(
+          content::NOTIFICATION_REPOST_WARNING_SHOWN,
+          content::Source<NavigationController>(this),
+          content::NotificationService::NoDetails());
+    }
     pending_reload_ = reload_type;
     web_contents_->Activate();
+    // TODO(sgurun): change the name to onFormResubmission http://crbug/156461
     web_contents_->GetDelegate()->ShowRepostFormWarningDialog(web_contents_);
   } else {
     DiscardNonCommittedEntriesInternal();
 
     NavigationEntryImpl* entry = entries_[current_index].get();
     SiteInstanceImpl* site_instance = entry->site_instance();
     DCHECK(site_instance);
 
     // If we are reloading an entry that no longer belongs to the current
     // site instance (for example, refreshing a page for just installed app),
@@ skipping 1290 matching lines @@
                       linked_ptr<NavigationEntryImpl>(
                           new NavigationEntryImpl(*source.entries_[i])));
     }
   }
 }
 
 void NavigationControllerImpl::SetGetTimestampCallbackForTest(
     const base::Callback<base::Time()>& get_timestamp_callback) {
   get_timestamp_callback_ = get_timestamp_callback;
 }