Make it possible to build without enable_supervised_users.

chrome/browser/chrome_browser_main.cc

Index: chrome/browser/chrome_browser_main.cc
diff --git a/chrome/browser/chrome_browser_main.cc b/chrome/browser/chrome_browser_main.cc
index eafb51360e975e1973b4c655d02e7094fbe5e100..ddea948d46c5c7688f57c320ebbe4518611c5d68 100644
--- a/chrome/browser/chrome_browser_main.cc
+++ b/chrome/browser/chrome_browser_main.cc
@@ -60,7 +60,6 @@
 #include "chrome/browser/component_updater/recovery_improved_component_installer.h"
 #include "chrome/browser/component_updater/sth_set_component_installer.h"
 #include "chrome/browser/component_updater/subresource_filter_component_installer.h"
-#include "chrome/browser/component_updater/supervised_user_whitelist_installer.h"
 #include "chrome/browser/component_updater/widevine_cdm_component_installer.h"
 #include "chrome/browser/defaults.h"
 #include "chrome/browser/experiments/memory_ablation_experiment.h"
@@ -257,6 +256,10 @@
 #include "components/rlz/rlz_tracker.h"
 #endif  // BUILDFLAG(ENABLE_RLZ)
 
+#if BUILDFLAG(ENABLE_SUPERVISED_USERS)
+#include "chrome/browser/component_updater/supervised_user_whitelist_installer.h"
+#endif
+
 #if BUILDFLAG(ENABLE_WEBRTC)
 #include "chrome/browser/media/webrtc/webrtc_log_util.h"
 #endif  // BUILDFLAG(ENABLE_WEBRTC)
@@ -494,9 +497,11 @@ void RegisterComponentsForUpdate() {
     g_browser_process->pnacl_component_installer()->RegisterPnaclComponent(cus);
 #endif  // !defined(DISABLE_NACL) && !defined(OS_ANDROID)
 
+#if BUILDFLAG(ENABLE_SUPERVISED_USERS)
   component_updater::SupervisedUserWhitelistInstaller* whitelist_installer =
       g_browser_process->supervised_user_whitelist_installer();
   whitelist_installer->RegisterComponents();
+#endif
 
   RegisterSubresourceFilterComponent(cus);