To reproduce the bug:
- Create a partner.
- Set it state "Alaska".
- Country becomes "United States".
- Set a country for YourCompany, such as Spain.
- Create a partner.
- Set it state "Alaska".
- Country remains blank.
Also, `node.xpath("//field")` was running over every `<field>` in the
view, not just those inside the `<div class="address_format">`. Now it
only traverses the right nodes, which renders every affected view
faster.