Autocomplete select another contact on registration and contribution pages doesn't set State/Province if contact's country is not the default country

Two related bugs:

1. Online contribution form and event registration form do not set default State / Province when the form loads for anonymous access (i.e. no contact_id to load address data from). Only the default Country is set.

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2. If > 1 country is enabled, and you are filling in event registration for another contact (civicrm/event/register?id=1&cid=0) ... the contact's billing address is pre-filled properly EXCEPT the State/Province field is NOT prefilled if their billing Country is not the default country.

The reason is that the State/Province options still contain the states belonging to the default country so there is no match for the contact's State value (it isn't present in the select list).

Seems like we need to trigger reload of the State/Province list based on the Country of the address we are filling defaults for.

NOTE: We do handle this properly if defaults are filled by using cid=NN in the URL (rather than selecting the contact from the autocomplete field).