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

third_party/libaddressinput/chromium/chrome_address_validator.h

Index: third_party/libaddressinput/chromium/chrome_address_validator.h
diff --git a/third_party/libaddressinput/chromium/chrome_address_validator.h b/third_party/libaddressinput/chromium/chrome_address_validator.h
index 43a4a4061ccbe3d5bf1caa2d99808341d71201dd..7a2c7c6f72bde9b3daa0dea85ff4956d03e4a883 100644
--- a/third_party/libaddressinput/chromium/chrome_address_validator.h
+++ b/third_party/libaddressinput/chromium/chrome_address_validator.h
@@ -94,6 +94,13 @@ class AddressValidator {
   // 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.
   //