[Autofill] [Butter] Add No thanks button to save card dialog

This CL patched another CL by jsaul@
https://chromium-review.googlesource.com/c/chromium/src/+/1334834

1) Added No thanks button as required by legal.
2) Changed the title to better explain its usage.

Uploaded screenshot in the bug comment#4.

Bug: 905393
Change-Id: Idc6e2e89a9cad9d4f5530ea4d4a1b2731feeff5e
Reviewed-on: https://chromium-review.googlesource.com/c/1343281
Reviewed-by: Fabio Tirelo <[email protected]>
Reviewed-by: Elly Fong-Jones <[email protected]>
Reviewed-by: Evan Stade <[email protected]>
Commit-Queue: Fabio Tirelo <[email protected]>
Cr-Commit-Position: refs/heads/master@{#610237}
diff --git a/chrome/browser/about_flags.cc b/chrome/browser/about_flags.cc
index b2b8ebd..237ddbf86 100644
--- a/chrome/browser/about_flags.cc
+++ b/chrome/browser/about_flags.cc
@@ -3020,6 +3020,12 @@
      kOsDesktop,
      FEATURE_VALUE_TYPE(
          autofill::features::kAutofillSaveCardDialogUnlabeledExpirationDate)},
+    {"enable-autofill-save-card-improved-user-consent",
+     flag_descriptions::kEnableAutofillSaveCardImprovedUserConsentName,
+     flag_descriptions::kEnableAutofillSaveCardImprovedUserConsentDescription,
+     kOsDesktop,
+     FEATURE_VALUE_TYPE(
+         autofill::features::kAutofillSaveCardImprovedUserConsent)},
     {"enable-autofill-save-card-sign-in-after-local-save",
      flag_descriptions::kEnableAutofillSaveCardSignInAfterLocalSaveName,
      flag_descriptions::kEnableAutofillSaveCardSignInAfterLocalSaveDescription,