Update Autofill Private API to provide a list of available countries.

chrome/browser/extensions/api/autofill_private/autofill_private_api.h

Index: chrome/browser/extensions/api/autofill_private/autofill_private_api.h
diff --git a/chrome/browser/extensions/api/autofill_private/autofill_private_api.h b/chrome/browser/extensions/api/autofill_private/autofill_private_api.h
index 9a34697c635f8f523e7244aee512ff8e783ef593..db7e98cfc25939f598c25d456da7b0c8634c7885 100644
--- a/chrome/browser/extensions/api/autofill_private/autofill_private_api.h
+++ b/chrome/browser/extensions/api/autofill_private/autofill_private_api.h
@@ -31,6 +31,24 @@ class AutofillPrivateSaveAddressFunction : public UIThreadExtensionFunction {
   DISALLOW_COPY_AND_ASSIGN(AutofillPrivateSaveAddressFunction);
 };
 
+class AutofillPrivateGetCountryListFunction : public UIThreadExtensionFunction {
+ public:
+  AutofillPrivateGetCountryListFunction();
+  DECLARE_EXTENSION_FUNCTION("autofillPrivate.getCountryList",
+                             AUTOFILLPRIVATE_GETCOUNTRYLIST);
+
+ protected:
+  ~AutofillPrivateGetCountryListFunction() override;
+
+  // ExtensionFunction overrides.
+  ResponseAction Run() override;
+
+ private:
+  ChromeExtensionFunctionDetails chrome_details_;
+
+  DISALLOW_COPY_AND_ASSIGN(AutofillPrivateGetCountryListFunction);
+};
+
 class AutofillPrivateGetAddressComponentsFunction :
     public UIThreadExtensionFunction {
  public: