Add country combobox to change country and rebuild address inputs.

chrome/browser/ui/autofill/country_combobox_model.h

Index: chrome/browser/ui/autofill/country_combobox_model.h
diff --git a/chrome/browser/ui/autofill/country_combobox_model.h b/chrome/browser/ui/autofill/country_combobox_model.h
index 74afeaee8a927b6a367c41197684dc2f8dcff032..cdeb954824a67219a2f31ea1e302a0658e31d1de 100644
--- a/chrome/browser/ui/autofill/country_combobox_model.h
+++ b/chrome/browser/ui/autofill/country_combobox_model.h
@@ -5,6 +5,7 @@
 #ifndef CHROME_BROWSER_UI_AUTOFILL_COUNTRY_COMBOBOX_MODEL_H_
 #define CHROME_BROWSER_UI_AUTOFILL_COUNTRY_COMBOBOX_MODEL_H_
 
+#include <string>
 #include <vector>
 
 #include "base/compiler_specific.h"
@@ -32,11 +33,29 @@ class CountryComboboxModel : public ui::ComboboxModel {
     return countries_.get();
   }
 
+  // Changes |selected_index_| to |index| after checking that it's sane.
+  void SelectIndex(int index);
+
+  // Changes |selected_index_| to the default index of this model.
+  void SelectDefaultIndex();
+
+  // Changes |selected_index_| to the index of |country_code|.
+  void SelectCountry(const std::string& country_code);
+
+  // Returns the currently selected country code for this model.
+  std::string GetSelectedCountryCode() const;
+
+  // Whether the default index is currently selected.
+  bool IsDefaultIndexSelected() const;
+
  private:
   // The countries to show in the model, including NULL for entries that are
   // not countries (the separator entry).
   ScopedVector<AutofillCountry> countries_;
 
+  // The index of the currently selected country.
+  int selected_index_;
+
   DISALLOW_COPY_AND_ASSIGN(CountryComboboxModel);
 };