Move session service and supervised users to buildflags.

chrome/browser/ui/startup/startup_browser_creator_browsertest.cc

Index: chrome/browser/ui/startup/startup_browser_creator_browsertest.cc
diff --git a/chrome/browser/ui/startup/startup_browser_creator_browsertest.cc b/chrome/browser/ui/startup/startup_browser_creator_browsertest.cc
index 0af6ec02dcce706c07ec59fb83de8f56b1e876d3..76cb4bb9c25885f8dce378755fb83b739febbc7e 100644
--- a/chrome/browser/ui/startup/startup_browser_creator_browsertest.cc
+++ b/chrome/browser/ui/startup/startup_browser_creator_browsertest.cc
@@ -41,6 +41,7 @@
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/extensions/extension_constants.h"
+#include "chrome/common/features.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/common/url_constants.h"
 #include "chrome/test/base/in_process_browser_test.h"
@@ -71,7 +72,7 @@ using testing::_;
 using testing::Return;
 #endif  // !defined(OS_CHROMEOS)
 
-#if defined(ENABLE_SUPERVISED_USERS)
+#if BUILDFLAG(ENABLE_SUPERVISED_USERS)
 #include "chrome/browser/supervised_user/supervised_user_navigation_observer.h"
 #include "chrome/browser/supervised_user/supervised_user_service.h"
 #include "chrome/browser/supervised_user/supervised_user_service_factory.h"