Refactors cvc and expiration date validation in CC upload logic as well as unmask prompt.

components/autofill/core/browser/validation.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/validation.h"
 
 #include <stddef.h>
 
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_piece.h"
@@ skipping 69 matching lines @@
       sum += digit / 10 + digit % 10;
     } else {
       sum += digit;
     }
     odd = !odd;
   }
 
   return (sum % 10) == 0;
 }
 
-bool IsValidCreditCardSecurityCode(const base::string16& text) {
-  if (text.size() < 3U || text.size() > 4U)
-    return false;
-
-  for (const base::char16& it : text) {
-    if (!base::IsAsciiDigit(it))
-      return false;
-  }
-  return true;
-}
-
 bool IsValidCreditCardSecurityCode(const base::string16& code,
-                                   const base::string16& number) {
-  const char* const type = CreditCard::GetCreditCardType(number);
-  size_t required_length = 3;
-  if (type == kAmericanExpressCard)
-    required_length = 4;
-
-  return code.length() == required_length;
+                                   const base::StringPiece card_type) {
+  size_t required_length = card_type == kAmericanExpressCard ? 4 : 3;
+  return code.length() == required_length &&
+         base::ContainsOnlyChars(code, base::ASCIIToUTF16("0123456789"));
 }
 
 bool IsValidEmailAddress(const base::string16& text) {
   // E-Mail pattern as defined by the WhatWG. (4.10.7.1.5 E-Mail state)
   const base::string16 kEmailPattern = base::ASCIIToUTF16(
       "^[a-zA-Z0-9.!#$%&'*+/=?^_`{|}~-]+@"
       "[a-zA-Z0-9-]+(?:\\.[a-zA-Z0-9-]+)*$");
   return MatchesPattern(text, kEmailPattern);
 }
 
@@ skipping 63 matching lines @@
                                              number_string.begin() + 9),
                          &serial)
       || serial == 0) {
     return false;
   }
 
   return true;
 }
 
 }  // namespace autofill