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

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

 // 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 62 matching lines @@
   for (std::string::const_iterator current = format.begin(),
                                    next = format.begin() + 1;
        current != format.end() && next != format.end();
        ++current, ++next) {
     if (IsTokenPrefix(*current) && IsToken(*next)) {
       fields->push_back(ParseToken(*next));
     }
   }
 }
 
+void ParseAddressFieldsRequired(const std::string& required,
+                                std::vector<AddressField>* fields) {
+  assert(fields != NULL);
+  fields->clear();
+  for (std::string::const_iterator token = required.begin();
+       token != required.end(); ++token) {
+    if (IsToken(*token)) {
+      fields->push_back(ParseToken(*token));
+    }
+  }
+}
+
 }  // namespace addressinput
 }  // namespace i18n