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 0a30e2daef3db931970d48eeb479509ccc244be5..dfe38e85f0fe5c69e5f398dd1133c2a0e140d07f 100644
--- a/chrome/browser/about_flags.cc
+++ b/chrome/browser/about_flags.cc
@@ -877,6 +877,13 @@ 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;