I'm using a Client Scripts to calll CustomEvent.fireAll and getting error "(g_env) [SCRIPT:EXEC] Error while running Client Script "IPFX  Open Frame": TypeError: CustomEvent.fireAll is not a function"

function onLoad() {
	var a = g_user.userID;
   alert(a);
//Type appropriate comment here, and begin script below
   var context = { "payload": a, "method": "openframe_communication" };
   CustomEvent.fireAll("openframe_request", context);
}