Speculative revert to see if this change introduced a performance regression on Mac intl perf bots.

chrome/browser/sessions/tab_restore_service.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/sessions/tab_restore_service.h"
 
 #include <algorithm>
 #include <iterator>
 #include <map>
 
@@ skipping 201 matching lines @@
 }
 
 void TabRestoreService::AddObserver(TabRestoreServiceObserver* observer) {
   observer_list_.AddObserver(observer);
 }
 
 void TabRestoreService::RemoveObserver(TabRestoreServiceObserver* observer) {
   observer_list_.RemoveObserver(observer);
 }
 
-void TabRestoreService::CreateHistoricalTab(content::WebContents* contents,
+void TabRestoreService::CreateHistoricalTab(NavigationController* tab,
                                             int index) {
   if (restoring_)
     return;
 
   TabRestoreServiceDelegate* delegate =
-      TabRestoreServiceDelegate::FindDelegateForWebContents(contents);
+      TabRestoreServiceDelegate::FindDelegateForController(tab, NULL);
   if (closing_delegates_.find(delegate) != closing_delegates_.end())
     return;
 
   scoped_ptr<Tab> local_tab(new Tab());
-  PopulateTab(local_tab.get(), index, delegate, &contents->GetController());
+  PopulateTab(local_tab.get(), index, delegate, tab);
   if (local_tab->navigations.empty())
     return;
 
   AddEntry(local_tab.release(), true, true);
 }
 
 void TabRestoreService::BrowserClosing(TabRestoreServiceDelegate* delegate) {
   closing_delegates_.insert(delegate);
 
   scoped_ptr<Window> window(new Window());
@@ skipping 1000 matching lines @@
   // the front, not the end and we just added the entries to the end).
   entries_to_write_ = staging_entries_.size();
 
   PruneEntries();
   NotifyTabsChanged();
 }
 
 Time TabRestoreService::TimeNow() const {
   return time_factory_ ? time_factory_->TimeNow() : Time::Now();
 }