libaddressinput: Add fallback data for US address validation.

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

-// Copyright (C) 2013 Google Inc.
+// Copyright (C) 2014 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,
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#ifndef I18N_ADDRESSINPUT_REGION_DATA_CONSTANTS_H_
-#define I18N_ADDRESSINPUT_REGION_DATA_CONSTANTS_H_
-
 #include <string>
-#include <vector>
 
 namespace i18n {
 namespace addressinput {
 
-class RegionDataConstants {
+class FallbackDataStore {
  public:
-  static const std::vector<std::string>& GetRegionCodes();
-  static const std::string& GetRegionData(const std::string& region_code);
-  static const std::string& GetDefaultRegionData();
+  // Gets default data for |key|. Should only be used as a last resort after
+  // attempts to check the local cache or the webserver have failed.
+  static bool Get(const std::string& key, std::string* data);
 };
 
 }  // namespace addressinput
 }  // namespace i18n
-
-#endif  // I18N_ADDRESSINPUT_REGION_DATA_CONSTANTS_H_