[Autofill] Move IsValidState() into validation.h

components/autofill/browser/validation.h

 // Copyright (c) 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.
 
 #ifndef COMPONENTS_AUTOFILL_BROWSER_VALIDATION_H_
 #define COMPONENTS_AUTOFILL_BROWSER_VALIDATION_H_
 
 #include "base/string16.h"
 
 namespace base {
@@ skipping 16 matching lines @@
 bool IsValidCreditCardSecurityCode(const base::string16& text);
 
 // Returns true if |code| looks like a valid credit card security code
 // for the type of credit card designated by |number|.
 bool IsValidCreditCardSecurityCode(const base::string16& code,
                                    const base::string16& number);
 
 // Returns true if |text| looks like a valid e-mail address.
 bool IsValidEmailAddress(const base::string16& text);
 
+// Returns true if |text| is a valid US state name or abbreviation.  It is
+// case insensitive.  Valid for US states only.
+bool IsValidState(const base::string16& text);
+
 // Returns true if |text| looks like a valid zip code.
 // Valid for US zip codes only.
 bool IsValidZip(const base::string16& text);
 
 }  // namespace autofill
 
 #endif  // COMPONENTS_AUTOFILL_BROWSER_VALIDATION_H_