Complete r1583026, sequel of "Focus input(dropdown list) when click on label in widget form" https://issues.apache.org/jira/browse/OFBIZ-5594. Thanks to Wei Zhang's report

git-svn-id: https://svn.apache.org/repos/asf/ofbiz/trunk@1584552 13f79535-47bb-0310-9956-ffa450edef68