[rac] Parse postal code formats and required fields in libaddressinput.

third_party/libaddressinput/chromium/cpp/src/address_field_util.h

 // Copyright (C) 2013 Google Inc.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 // http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
@@ skipping 18 matching lines @@
   NEWLINE = -1
 };
 
 // Clears |fields|, parses |format|, and adds the format address fields to
 // |fields|. The |fields| may also contain NEWLINE elements. For example, parses
 // "%S%C%n%D%X" into {ADMIN_AREA, LOCALITY, NEWLINE, DEPENDENT_LOCALITY,
 // SORTING_CODE}.
 void ParseAddressFieldsFormat(const std::string& format,
                               std::vector<AddressField>* fields);
 
+// Clears |fields|, parses |required|, and adds the required fields to |fields|.
+// For example, parses "SCDX" into {ADMIN_AREA, LOCALITY, DEPENDENT_LOCALITY,
+// SORTING_CODE}.
+void ParseAddressFieldsRequired(const std::string& required,
+                                std::vector<AddressField>* fields);
+
 }  // namespace addressinput
 }  // namespace i18n
 
 #endif  // I18N_ADDRESSINPUT_ADDRESS_FIELD_UTIL_H_