[widgets] test "bn" in error

# bn (download, files)
Tests the UA's ability to deal with custom icon declarations in the config document and matching default icons. To pass, the icons list must contain a pointer to "icons/pass.png", and "locales/en/icon.jpg" (ordering of the items in the list is irrelevant).


The actual icons included are "icons/pass.png" and "locales/en/icon.png" (not .jpg).