[Autofill] Add upstreaming UKM

ios/chrome/browser/ui/autofill/autofill_client_ios.mm

Index: ios/chrome/browser/ui/autofill/autofill_client_ios.mm
diff --git a/ios/chrome/browser/ui/autofill/autofill_client_ios.mm b/ios/chrome/browser/ui/autofill/autofill_client_ios.mm
index 562998cfccd3c913de78d2bf917f95a41638dd11..99b7a2d67808fc1bd9191d18806bfb67e9f1284a 100644
--- a/ios/chrome/browser/ui/autofill/autofill_client_ios.mm
+++ b/ios/chrome/browser/ui/autofill/autofill_client_ios.mm
@@ -80,6 +80,10 @@ rappor::RapporServiceImpl* AutofillClientIOS::GetRapporServiceImpl() {
   return GetApplicationContext()->GetRapporServiceImpl();
 }
 
+ukm::UkmService* AutofillClientIOS::GetUkmService() {
+  return GetApplicationContext()->GetUkmService();
+}
+
 void AutofillClientIOS::ShowAutofillSettings() {
   NOTREACHED();
 }