Revert of Implement inline signin with iframe

chrome/browser/ui/webui/signin/inline_login_ui.cc

 // Copyright 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/ui/webui/signin/inline_login_ui.h"
 
-#include "chrome/browser/extensions/extension_web_contents_observer.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/common/url_constants.h"
 #include "content/public/browser/web_ui.h"
 #include "content/public/browser/web_ui_data_source.h"
 #include "grit/browser_resources.h"
 #include "grit/chromium_strings.h"
 #if defined(OS_CHROMEOS)
 #include "chrome/browser/ui/webui/chromeos/login/inline_login_handler_chromeos.h"
 #else
 #include "chrome/browser/extensions/tab_helper.h"
 #include "chrome/browser/ui/webui/signin/inline_login_handler_impl.h"
 #endif
 
 namespace {
 
 content::WebUIDataSource* CreateWebUIDataSource() {
   content::WebUIDataSource* source =
         content::WebUIDataSource::Create(chrome::kChromeUIChromeSigninHost);
-  source->OverrideContentSecurityPolicyFrameSrc("frame-src chrome-extension:;");
   source->SetUseJsonJSFormatV2();
   source->SetJsonPath("strings.js");
 
   source->SetDefaultResource(IDR_INLINE_LOGIN_HTML);
   source->AddResourcePath("inline_login.css", IDR_INLINE_LOGIN_CSS);
   source->AddResourcePath("inline_login.js", IDR_INLINE_LOGIN_JS);
 
   source->AddLocalizedString("title", IDS_CHROME_SIGNIN_TITLE);
   return source;
 };
 
 } // empty namespace
 
 InlineLoginUI::InlineLoginUI(content::WebUI* web_ui)
     : WebDialogUI(web_ui),
       auth_extension_(Profile::FromWebUI(web_ui)) {
   Profile* profile = Profile::FromWebUI(web_ui);
   content::WebUIDataSource::Add(profile, CreateWebUIDataSource());
 
 #if defined(OS_CHROMEOS)
   web_ui->AddMessageHandler(new chromeos::InlineLoginHandlerChromeOS());
 #else
   web_ui->AddMessageHandler(new InlineLoginHandlerImpl());
   // Required for intercepting extension function calls when the page is loaded
   // in a bubble (not a full tab, thus tab helpers are not registered
   // automatically).
-  extensions::ExtensionWebContentsObserver::CreateForWebContents(
-      web_ui->GetWebContents());
+  extensions::TabHelper::CreateForWebContents(web_ui->GetWebContents());
 #endif
 }
 
 InlineLoginUI::~InlineLoginUI() {}