https://issues.apache.org/jira/browse/EXTCDI-246 adding a chained wrapper function which fixes the issue
myfaces/extensions/cdi/trunk/examples/jsf-playground/clientside_windowhandler_jsf20/src/main/webapp/resources/scripts/
myfaces/extensions/cdi/trunk/examples/jsf-playground/clientside_windowhandler_jsf20/src/main/webapp/resources/scripts/windowhandler.js