Make TabContents ctor private; poke hole for existing callers.

chrome/browser/ui/webui/constrained_web_dialog_delegate_base.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 "chrome/browser/ui/webui/constrained_web_dialog_delegate_base.h"
 
 #include <string>
 
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/constrained_window.h"
@@ skipping 15 matching lines @@
     WebDialogDelegate* delegate,
     WebDialogWebContentsDelegate* tab_delegate)
     : WebDialogWebContentsDelegate(profile, new ChromeWebContentsHandler),
       web_dialog_delegate_(delegate),
       window_(NULL),
       closed_via_webui_(false),
       release_tab_on_close_(false) {
   CHECK(delegate);
   WebContents* web_contents =
       WebContents::Create(profile, NULL, MSG_ROUTING_NONE, NULL);
-  tab_.reset(new TabContents(web_contents));
+  tab_.reset(TabContents::Factory::CreateTabContents(web_contents));
   if (tab_delegate) {
     override_tab_delegate_.reset(tab_delegate);
     web_contents->SetDelegate(tab_delegate);
   } else {
     web_contents->SetDelegate(this);
   }
   // Set |this| as a delegate so the ConstrainedWebDialogUI can retrieve it.
   ConstrainedWebDialogUI::SetConstrainedDelegate(web_contents, this);
 
   web_contents->GetController().LoadURL(delegate->GetDialogContentURL(),
@@ skipping 44 matching lines @@
 }
 
 TabContents* ConstrainedWebDialogDelegateBase::tab() {
   return tab_.get();
 }
 
 void ConstrainedWebDialogDelegateBase::HandleKeyboardEvent(
     content::WebContents* source,
     const NativeWebKeyboardEvent& event) {
 }