Convert RLZ to a buildflag header

chrome/browser/ui/app_list/app_list_controller_delegate.cc

Index: chrome/browser/ui/app_list/app_list_controller_delegate.cc
diff --git a/chrome/browser/ui/app_list/app_list_controller_delegate.cc b/chrome/browser/ui/app_list/app_list_controller_delegate.cc
index eef8d47a3aa3948e5b9f31485bbb9c17d2ecf015..fa717e49e21452477f4a1468c33da21d90d9513f 100644
--- a/chrome/browser/ui/app_list/app_list_controller_delegate.cc
+++ b/chrome/browser/ui/app_list/app_list_controller_delegate.cc
@@ -22,13 +22,14 @@
 #include "extensions/common/manifest_handlers/options_page_info.h"
 #include "extensions/common/manifest_url_handlers.h"
 #include "net/base/url_util.h"
+#include "rlz/features/features.h"
 #include "ui/app_list/app_list_folder_item.h"
 #include "ui/app_list/app_list_item.h"
 #include "ui/app_list/app_list_model.h"
 #include "ui/app_list/app_list_switches.h"
 #include "ui/gfx/geometry/rect.h"
 
-#if defined(ENABLE_RLZ)
+#if BUILDFLAG(ENABLE_RLZ)
 #include "components/rlz/rlz_tracker.h"  // nogncheck
 #endif
 
@@ -203,7 +204,7 @@ void AppListControllerDelegate::GetApps(Profile* profile,
 }
 
 void AppListControllerDelegate::OnSearchStarted() {
-#if defined(ENABLE_RLZ)
+#if BUILDFLAG(ENABLE_RLZ)
   rlz::RLZTracker::RecordAppListSearch();
 #endif
 }