Use TabLoader in TabRestoreService.

components/sessions/core/tab_restore_service_helper.cc

Index: components/sessions/core/tab_restore_service_helper.cc
diff --git a/components/sessions/core/tab_restore_service_helper.cc b/components/sessions/core/tab_restore_service_helper.cc
index bbb41f5e8b6da032254dbbc3f66ca648ac111ea3..76b8946267ecbe1ad9584ee82e12d26fb33b53b8 100644
--- a/components/sessions/core/tab_restore_service_helper.cc
+++ b/components/sessions/core/tab_restore_service_helper.cc
@@ -209,7 +209,6 @@ std::vector<LiveTab*> TabRestoreServiceHelper::RestoreEntryById(
               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);
@@ -477,7 +476,6 @@ LiveTabContext* TabRestoreServiceHelper::RestoreTab(
         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());