fix #303 Infinite loop on datepicker
fix #300 some tests are not referenced in a test suite
fix #312 Hard-coded dropdown skin class for the List in the MultiSelect and similar widgets
fix #315 AutoComplete JS error when clicking the dropdown button

Fixing a regression after b1eb1323439bc3f3203ef5b0c3880410105e8715 using
the similar solution as in 1c8d106816f790fa65465660ee9a6b9ab375af50.

Pull request #316.