[Autofill] Credit Card validation for rAc.

Validate all things credit card. (Number, CSC, Expiration)
BUG=170467


Review URL: https://chromiumcodereview.appspot.com/12213077

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@181861 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/chrome/browser/autofill/validation.h b/chrome/browser/autofill/validation.h
index f8e923b..93557b7 100644
--- a/chrome/browser/autofill/validation.h
+++ b/chrome/browser/autofill/validation.h
@@ -13,6 +13,9 @@
 // Uses the Luhn formula to validate the number.
 bool IsValidCreditCardNumber(const string16& text);
 
+// Returns true if |text| looks like a valid credit card security code.
+bool IsValidCreditCardSecurityCode(const string16& text);
+
 }  // namespace autofill
 
 #endif  // CHROME_BROWSER_AUTOFILL_VALIDATION_H_