We have a problem in the process on destroying WebContentsImpl because

chrome/browser/infobars/infobar_service.cc

 // Copyright (c) 2013 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/infobars/infobar_service.h"
 
 #include "base/command_line.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/infobars/insecure_content_infobar_delegate.h"
 #include "chrome/common/render_messages.h"
@@ skipping 89 matching lines @@
 
 void InfoBarService::RenderProcessGone(base::TerminationStatus status) {
   RemoveAllInfoBars(true);
 }
 
 void InfoBarService::NavigationEntryCommitted(
     const content::LoadCommittedDetails& load_details) {
   OnNavigation(NavigationDetailsFromLoadCommittedDetails(load_details));
 }
 
-void InfoBarService::WebContentsDestroyed(content::WebContents* web_contents) {
+void InfoBarService::WebContentsDestroyed() {
   // The WebContents is going away; be aggressively paranoid and delete
   // ourselves lest other parts of the system attempt to add infobars or use
   // us otherwise during the destruction.
-  web_contents->RemoveUserData(UserDataKey());
+  web_contents()->RemoveUserData(UserDataKey());
   // That was the equivalent of "delete this". This object is now destroyed;
   // returning from this function is the only safe thing to do.
 }
 
 bool InfoBarService::OnMessageReceived(const IPC::Message& message) {
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(InfoBarService, message)
     IPC_MESSAGE_HANDLER(ChromeViewHostMsg_DidBlockDisplayingInsecureContent,
                         OnDidBlockDisplayingInsecureContent)
     IPC_MESSAGE_HANDLER(ChromeViewHostMsg_DidBlockRunningInsecureContent,
                         OnDidBlockRunningInsecureContent)
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
   return handled;
 }
 
 void InfoBarService::OnDidBlockDisplayingInsecureContent() {
   InsecureContentInfoBarDelegate::Create(
       this, InsecureContentInfoBarDelegate::DISPLAY);
 }
 
 void InfoBarService::OnDidBlockRunningInsecureContent() {
   InsecureContentInfoBarDelegate::Create(this,
                                          InsecureContentInfoBarDelegate::RUN);
 }