Return webcontents and add in test.

chrome/browser/ui/browser_tabrestore.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/browser_tabrestore.h"
 
 #include "chrome/browser/extensions/tab_helper.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/sessions/session_service.h"
 #include "chrome/browser/sessions/session_service_factory.h"
@@ skipping 112 matching lines @@
         browser->window()->GetRestoredBounds().size());
     web_contents->WasHidden();
   }
   SessionService* session_service =
       SessionServiceFactory::GetForProfileIfExisting(browser->profile());
   if (session_service)
     session_service->TabRestored(web_contents, pin);
   return web_contents;
 }
 
-void ReplaceRestoredTab(
+content::WebContents* ReplaceRestoredTab(
     Browser* browser,
     const std::vector<SerializedNavigationEntry>& navigations,
     int selected_navigation,
     bool from_last_session,
     const std::string& extension_app_id,
     content::SessionStorageNamespace* session_storage_namespace,
     const std::string& user_agent_override) {
   WebContents* web_contents = CreateRestoredTab(browser,
                                                 navigations,
                                                 selected_navigation,
                                                 extension_app_id,
                                                 from_last_session,
                                                 session_storage_namespace,
                                                 user_agent_override);
 
   // ReplaceWebContentsAt won't animate in the restoration, so manually do the
   // equivalent of ReplaceWebContentsAt.
   TabStripModel* tab_strip = browser->tab_strip_model();
   int insertion_index = tab_strip->active_index();
   tab_strip->InsertWebContentsAt(insertion_index + 1,
                                  web_contents,
                                  TabStripModel::ADD_ACTIVE |
                                  TabStripModel::ADD_INHERIT_GROUP);
   tab_strip->CloseWebContentsAt(insertion_index, TabStripModel::CLOSE_NONE);
+  return web_contents;
 }
 
 }  // namespace chrome