Enable NTPTilesInInstantService by default

chrome/browser/ui/toolbar/back_forward_menu_model_unittest.cc

Index: chrome/browser/ui/toolbar/back_forward_menu_model_unittest.cc
diff --git a/chrome/browser/ui/toolbar/back_forward_menu_model_unittest.cc b/chrome/browser/ui/toolbar/back_forward_menu_model_unittest.cc
index 5d66a187d071cad5a77b48f9788e86dfaed3da5b..48395cb324895e689211f529b42b45ba44b00d6c 100644
--- a/chrome/browser/ui/toolbar/back_forward_menu_model_unittest.cc
+++ b/chrome/browser/ui/toolbar/back_forward_menu_model_unittest.cc
@@ -565,6 +565,4 @@ TEST_F(BackFwdMenuModelTest, FaviconLoadTest) {
 
   // Make sure the browser deconstructor doesn't have problems.
   browser->tab_strip_model()->CloseAllTabs();
-  // This is required to prevent the message loop from hanging.
-  profile()->DestroyHistoryService();
 }