Look in all available CVC fields for a value for credit card upload.

components/autofill/core/browser/autofill_manager.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/autofill/core/browser/autofill_manager.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 1057 matching lines @@
     // this block can be reached on observing either a new card or one already
     // stored locally. We will offer to upload either kind.
     upload_request_ = payments::PaymentsClient::UploadRequestDetails();
     upload_request_.card = *imported_credit_card;
 
     // Check for a CVC to determine whether we can prompt the user to upload
     // their card. If no CVC is present, do nothing. We could fall back to a
     // local save but we believe that sometimes offering upload and sometimes
     // offering local save is a confusing user experience.
     for (const AutofillField* field : submitted_form) {
-      if (field->Type().GetStorableType() == CREDIT_CARD_VERIFICATION_CODE) {
+      if (field->Type().GetStorableType() == CREDIT_CARD_VERIFICATION_CODE &&
+          !field->value.empty()) {

[Mathieu, 2016/04/20 20:00:41]

note that this is still not fully robust (some fields will have "___" or some
stuff) but it's probably good. You could also try to StringToInt it. Up to you.

[Justin Donnelly, 2016/04/20 20:58:01]

Good idea. Done.

         upload_request_.cvc = field->value;
         break;
       }
     }
     if (upload_request_.cvc.empty()) {
       AutofillMetrics::LogCardUploadDecisionMetric(
           AutofillMetrics::UPLOAD_NOT_OFFERED_NO_CVC);
       return;
     }
 
@@ skipping 928 matching lines @@
     if (i > 0)
       fputs("Next oldest form:\n", file);
   }
   fputs("\n", file);
 
   fclose(file);
 }
 #endif  // ENABLE_FORM_DEBUG_DUMP
 
 }  // namespace autofill