[Autofill Auth UI] Adding experiment flag for card unmask prompt changes

Bug: 991037
Change-Id: I5fda90d7d4f5c415d66e6e972a446e83e92ee764
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1737815
Commit-Queue: Siyu An <[email protected]>
Reviewed-by: Jared Saul <[email protected]>
Cr-Commit-Position: refs/heads/master@{#684537}
diff --git a/chrome/browser/about_flags.cc b/chrome/browser/about_flags.cc
index 1e90b149..bdfe7c8c 100644
--- a/chrome/browser/about_flags.cc
+++ b/chrome/browser/about_flags.cc
@@ -4311,6 +4311,13 @@
      flag_descriptions::kPolicyAtomicGroupsEnabledDescription, kOsAll,
      FEATURE_VALUE_TYPE(policy::features::kPolicyAtomicGroup)},
 
+    {"enable-autofill-updated-card-unmask-prompt-ui",
+     flag_descriptions::kEnableAutofillUpdatedCardUnmaskPromptUiName,
+     flag_descriptions::kEnableAutofillUpdatedCardUnmaskPromptUiDescription,
+     kOsDesktop,
+     FEATURE_VALUE_TYPE(
+         autofill::features::kAutofillUpdatedCardUnmaskPromptUi)},
+
     // NOTE: Adding a new flag requires adding a corresponding entry to enum
     // "LoginCustomFlags" in tools/metrics/histograms/enums.xml. See "Flag
     // Histograms" in tools/metrics/histograms/README.md (run the