un-fsck themeTester.html

[alex]

themeTester.html has been b0rken for several days due to colliding widget IDs. Why this situation throws an exception instead of console.warn()-ing, I don't know, but the theme test page shouldn't duplicate ids.

[bill]

Already fixed in [10495]. It's an error because it causes the problem closing the drop down from Combobox (and because in general two items with the same primary key is considered an error).