API Name: global.SystemAddressFilterUtil

var SystemAddressFilterUtil = Class.create();
SystemAddressFilterUtil.prototype = Object.extendsObject(AbstractAjaxProcessor, {
isAssignedToEmailAccount: function() {
var gr = new GlideRecordSecure('sys_email_account');
gr.addQuery('system_address_filter', this.getParameter('sysparm_filter_id'));
gr.query();

return gr.hasNext();
},

type: 'SystemAddressFilterUtil'
});