Update Chrome Upstream flow (Chrome -> Payments upload credit card save for Autofill) to reflect new UI mocks

Mocks: https://docs.google.com/presentation/d/135dRphfYbqnbdWqsHf2Kjth1HzMjidKwLq94i-0RCOQ/edit#slide=id.g1e6c4c1b7a_2_49

BUG=736944

Review-Url: https://codereview.chromium.org/2955963002
Cr-Commit-Position: refs/heads/master@{#493080}
diff --git a/chrome/browser/about_flags.cc b/chrome/browser/about_flags.cc
index 5c94611..0844a81 100644
--- a/chrome/browser/about_flags.cc
+++ b/chrome/browser/about_flags.cc
@@ -2876,6 +2876,10 @@
      flag_descriptions::kEnableAutofillCreditCardUploadCvcPromptDescription,
      kOsDesktop,
      FEATURE_VALUE_TYPE(autofill::kAutofillUpstreamRequestCvcIfMissing)},
+    {"enable-autofill-credit-card-upload-new-ui",
+     flag_descriptions::kEnableAutofillCreditCardUploadNewUiName,
+     flag_descriptions::kEnableAutofillCreditCardUploadNewUiDescription,
+     kOsDesktop, FEATURE_VALUE_TYPE(autofill::kAutofillUpstreamShowNewUi)},
     {"enable-autofill-credit-card-bank-name-display",
      flag_descriptions::kEnableAutofillCreditCardBankNameDisplayName,
      flag_descriptions::kEnableAutofillCreditCardBankNameDisplayDescription,