(hotfix) some minor style/convention cleanups to OptionListDropdown
(hotfix) some minor style/convention cleanups to OptionListDropdown

I noticed these after reviewing Collin's changes in PR 162.  These
are just some minor style updates and convention changes - mostly
around not checking var event vars before calling stop propagation
or prevent default.

redding/romo,redding/romo,redding/romo