add all frontend files

node_modules/es-abstract/2020/ToInteger.js

@@ -0,0 +1,15 @@
+'use strict';
+
+var ES5ToInteger = require('../5/ToInteger');
+
+var ToNumber = require('./ToNumber');
+
+// https://262.ecma-international.org/11.0/#sec-tointeger
+
+module.exports = function ToInteger(value) {
+	var number = ToNumber(value);
+	if (number !== 0) {
+		number = ES5ToInteger(number);
+	}
+	return number === 0 ? 0 : number;
+};