export is not defined

[BinaryRyan]

Steps to reproduce

1.read xterm-headless from js file
2.run this script in v8 engine

ReferenceError: exports is not defined [recovered]

	iso := v8.NewIsolate()

	xtermScript, err := fileutil.ReadFileToString("../js/xterm-headless.js")
	if err != nil {
		panic(err)
	}

	ctx := v8.NewContext(iso)
	_, err = ctx.RunScript(xtermScript, "xterm-headless.js")
	if err != nil {
		panic(err)
	}

    var r = exports;
    for (var n in s) r[n] = s[n];
    s.__esModule && Object.defineProperty(r, "__esModule", {
        value: !0
    })