Use TabLoader in TabRestoreService.

components/sessions/core/tab_restore_service_helper.cc

 // Copyright 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 "components/sessions/core/tab_restore_service_helper.h"
 
 #include <inttypes.h>
 #include <stddef.h>
 
 #include <algorithm>
@@ skipping 191 matching lines @@
         context = client_->CreateLiveTabContext(window.app_name);
         for (size_t tab_i = 0; tab_i < window.tabs.size(); ++tab_i) {
           const Tab& tab = *window.tabs[tab_i];
           LiveTab* restored_tab = context->AddRestoredTab(
               tab.navigations, context->GetTabCount(),
               tab.current_navigation_index, tab.extension_app_id,
               static_cast<int>(tab_i) == window.selected_tab_index, tab.pinned,
               tab.from_last_session, tab.platform_data.get(),
               tab.user_agent_override);
           if (restored_tab) {
-            restored_tab->LoadIfNecessary();
             client_->OnTabRestored(
                 tab.navigations.at(tab.current_navigation_index).virtual_url());
             live_tabs.push_back(restored_tab);
           }
         }
         // All the window's tabs had the same former browser_id.
         if (auto browser_id = window.tabs[0]->browser_id) {
           UpdateTabBrowserIDs(browser_id, context->GetSessionID().id());
         }
       } else {
@@ skipping 247 matching lines @@
         disposition != WindowOpenDisposition::UNKNOWN) {
       tab_index = context->GetTabCount();
     }
 
     restored_tab = context->AddRestoredTab(
         tab.navigations, tab_index, tab.current_navigation_index,
         tab.extension_app_id,
         disposition != WindowOpenDisposition::NEW_BACKGROUND_TAB, tab.pinned,
         tab.from_last_session, tab.platform_data.get(),
         tab.user_agent_override);
-    restored_tab->LoadIfNecessary();
   }
   client_->OnTabRestored(
       tab.navigations.at(tab.current_navigation_index).virtual_url());
   if (live_tab)
     *live_tab = restored_tab;
 
   return context;
 }
 
 bool TabRestoreServiceHelper::ValidateTab(const Tab& tab) {
@@ skipping 60 matching lines @@
         tab.browser_id = new_id;
     }
   }
 }
 
 base::Time TabRestoreServiceHelper::TimeNow() const {
   return time_factory_ ? time_factory_->TimeNow() : base::Time::Now();
 }
 
 }  // namespace sessions