Use TabLoader in TabRestoreService.

components/sessions/ios/ios_live_tab.mm

Index: components/sessions/ios/ios_live_tab.mm
diff --git a/components/sessions/ios/ios_live_tab.mm b/components/sessions/ios/ios_live_tab.mm
index 5f8f7dda6bebf53fe0e2391d950c444679bb08e5..b34747af4d51dc762e6f2fc36df54f388c703892 100644
--- a/components/sessions/ios/ios_live_tab.mm
+++ b/components/sessions/ios/ios_live_tab.mm
@@ -54,10 +54,6 @@ int IOSLiveTab::GetEntryCount() {
   return navigation_manager()->GetItemCount();
 }
 
-void IOSLiveTab::LoadIfNecessary() {
-  navigation_manager()->LoadIfNecessary();
-}
-
 const std::string& IOSLiveTab::GetUserAgentOverride() const {
   // Dynamic user agent overrides are not supported on iOS.
   return user_agent_override_;