Make it possible to build without enable_supervised_users.

chrome/browser/ui/webui/interstitials/interstitial_ui.cc

Index: chrome/browser/ui/webui/interstitials/interstitial_ui.cc
diff --git a/chrome/browser/ui/webui/interstitials/interstitial_ui.cc b/chrome/browser/ui/webui/interstitials/interstitial_ui.cc
index 6841d01ce596eb0973fa52d83a9b29c92b73ddc6..be8eee62ee7fb2419c933ed8a5857c30bd842f3f 100644
--- a/chrome/browser/ui/webui/interstitials/interstitial_ui.cc
+++ b/chrome/browser/ui/webui/interstitials/interstitial_ui.cc
@@ -16,7 +16,6 @@
 #include "chrome/browser/safe_browsing/ui_manager.h"
 #include "chrome/browser/ssl/bad_clock_blocking_page.h"
 #include "chrome/browser/ssl/ssl_blocking_page.h"
-#include "chrome/browser/supervised_user/supervised_user_interstitial.h"
 #include "chrome/common/features.h"
 #include "chrome/common/url_constants.h"
 #include "components/grit/components_resources.h"
@@ -42,6 +41,10 @@
 #include "chrome/browser/ssl/captive_portal_blocking_page.h"
 #endif
 
+#if BUILDFLAG(ENABLE_SUPERVISED_USERS)
+#include "chrome/browser/supervised_user/supervised_user_interstitial.h"
+#endif
+
 using security_interstitials::TestSafeBrowsingBlockingPageQuiet;
 
 namespace {