Function isChildOf

codebase/sources/dhtmlxscheduler.js:12255–12260

(child, parent)

        return !!modalsStack.length;
      }
      function isChildOf(child, parent) {
        while (child && child != parent) {
          child = child.parentNode;
        }
        return !!(child == parent);
      }
      function afterPopup(box) {
        setTimeout(function() {
          if (scheduler2.$destroyed) {