Location Handler Filter Country throws an error on an exposed input

Problem/Motivation

This is a partial duplicate ticket, to forward port to the D7 branch of an issue I found in 6.x-3.3 branch at #2101509, where the intended location_handler_filter_location_country.inc for views, would place the exposed input values into an array, after the item was already set as one. My scenario was adding an exposed Country select field to a view. The output produced a SQL warning, and no return in the query, as it would set the value as an empty string.

Proposed resolution

My solution is the attached a patch that adds a check for the value type equaling an array, when the exposed input is being accepted. If set, no action is taken. The check also verifies that the input is a multi select, so it should not break any current views, nor reset any single value items.

Please let me know if I missed any scenarios or if the code could be more generic to cover more items.

Thanks! =-D