Thanks for the reply @anish-s This jscomp variable is coming from the
gcc compiler scripts I believe.Whenever languageIn=ECMASCRIPT_2015; is
used, it adds some extra code in clientlibs, and that's why this error.
l.r = function(e) { $jscomp.initSymbol(); $jscomp.initSymbol();
$jscomp.initSymbol(); "undefined" != typeof Symbol && Symbol.toStringTag
&& Object.defineProperty(e, Symbol.toStringTag, { value: "Module" }),
Object.defineProperty(e, "__esModule", { value: !0 }) }