[rAc] Reset the user's selection to the new default when the default Wallet item changes.

chrome/browser/ui/autofill/autofill_dialog_controller_impl.h

Index: chrome/browser/ui/autofill/autofill_dialog_controller_impl.h
diff --git a/chrome/browser/ui/autofill/autofill_dialog_controller_impl.h b/chrome/browser/ui/autofill/autofill_dialog_controller_impl.h
index 43e8eba330beba77ac5751f807554627f7bc80b6..f9e208ed6f1f7f4403687990356b14f878afc1fa 100644
--- a/chrome/browser/ui/autofill/autofill_dialog_controller_impl.h
+++ b/chrome/browser/ui/autofill/autofill_dialog_controller_impl.h
@@ -570,7 +570,12 @@ class AutofillDialogControllerImpl : public AutofillDialogViewDelegate,
   scoped_ptr<wallet::WalletItems> wallet_items_;
   scoped_ptr<wallet::FullWallet> full_wallet_;
 
-  // The last active instrument and shipping address object ids. These
+  // The default active instrument and shipping address object IDs as of the
+  // last time Wallet items were fetched. These variables are only set
+  // (i.e. non-empty) when the Wallet items are being re-fetched.
+  std::string previous_default_instrument_id_;
+  std::string previous_default_shipping_address_id_;
+  // The last active instrument and shipping address object IDs. These
   // variables are only set (i.e. non-empty) when the Wallet items are being
   // re-fetched.
   std::string previously_selected_instrument_id_;