Add a switch for enabling the WebsiteSettingsUI to the about:flags page.

chrome/browser/about_flags.cc

Index: chrome/browser/about_flags.cc
diff --git a/chrome/browser/about_flags.cc b/chrome/browser/about_flags.cc
index f44e77b238fc358c3a3fb4de43976e26ec56f347..12c139d41224c169fca55a3ad0bc00644384eee0 100644
--- a/chrome/browser/about_flags.cc
+++ b/chrome/browser/about_flags.cc
@@ -891,6 +891,13 @@ const Experiment kExperiments[] = {
     SINGLE_VALUE_TYPE(ash::switches::kAshDebugShortcuts),
   },
 #endif
+  {
+    "enable-website-settings",  // FLAGS:RECORD_UMA
+    IDS_FLAGS_ENABLE_WEBSITE_SETTINGS_NAME,
+    IDS_FLAGS_ENABLE_WEBSITE_SETTINGS_DESCRIPTION,
+    kOsAll,
+    SINGLE_VALUE_TYPE(switches::kEnableWebsiteSettings),
+  },
 };
 
 const Experiment* experiments = kExperiments;