[Reland] Use dropdown list for admin areas in pr form.

third_party/libaddressinput/chromium/chrome_address_validator.h

 // Copyright 2014 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 THIRD_PARTY_LIBADDRESSINPUT_CHROMIUM_CHROME_ADDRESS_VALIDATOR_H_
 #define THIRD_PARTY_LIBADDRESSINPUT_CHROMIUM_CHROME_ADDRESS_VALIDATOR_H_
 
 #include <stddef.h>
 
 #include <map>
@@ skipping 76 matching lines @@
   // localities. A typical data size is 10KB. The largest is 250KB. If a region
   // has language-specific validation rules, then these are also loaded.
   //
   // Example rule:
   // https://i18napis.appspot.com/ssl-aggregate-address/data/US
   //
   // If the rules are already in progress of being loaded, it does nothing.
   // Invokes |load_rules_listener| when the loading has finished.
   virtual void LoadRules(const std::string& region_code);
 
+  // Returns the list of sub-regions (recorded as sub-keys) of the region
+  // (recorded as rule) indicated by |region_code|. So, if the |region_code| is
+  // a country code, sub-region means the country's admin area.
+  // This function should be called when the rules are loaded.
+  virtual std::vector<std::string> GetRegionSubKeys(
+      const std::string& region_code);
+
   // Validates the |address| and populates |problems| with the validation
   // problems, filtered according to the |filter| parameter.
   //
   // If the |filter| is empty, then all discovered validation problems are
   // returned. If the |filter| contains problem elements, then only the problems
   // in the |filter| may be returned.
   virtual Status ValidateAddress(
       const ::i18n::addressinput::AddressData& address,
       const ::i18n::addressinput::FieldProblemMap* filter,
       ::i18n::addressinput::FieldProblemMap* problems) const;
@@ skipping 91 matching lines @@
   // any WeakPtrs to AddressValidator are invalidated before its members
   // variable's destructors are executed, rendering them invalid.
   base::WeakPtrFactory<AddressValidator> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(AddressValidator);
 };
 
 }  // namespace autofill
 
 #endif  // THIRD_PARTY_LIBADDRESSINPUT_CHROMIUM_CHROME_ADDRESS_VALIDATOR_H_