Add other variations (with ids) for NTPSnippets to chrome://flags

ios/chrome/browser/about_flags.mm

Index: ios/chrome/browser/about_flags.mm
diff --git a/ios/chrome/browser/about_flags.mm b/ios/chrome/browser/about_flags.mm
index e1aaa74a11c5daa8b429002418d60c04d18d084b..cde3c2b3d2e3cb3b316a2cc4bf7d36d4ecd5cf85 100644
--- a/ios/chrome/browser/about_flags.mm
+++ b/ios/chrome/browser/about_flags.mm
@@ -260,6 +260,13 @@ void ConvertFlagsToSwitches(flags_ui::FlagsStorage* flags_storage,
   AppendSwitchesFromExperimentalSettings(command_line);
 }
 
+std::vector<std::string> RegisterAllFeatureVariationParameters(
+    flags_ui::FlagsStorage* flags_storage,
+    base::FeatureList* feature_list) {
+  return FlagsStateSingleton::GetFlagsState()
+      ->RegisterAllFeatureVariationParameters(flags_storage, feature_list);
+}
+
 void GetFlagFeatureEntries(flags_ui::FlagsStorage* flags_storage,
                            flags_ui::FlagAccess access,
                            base::ListValue* supported_entries,