const favorite = 7 bug in ES5 way

```js
'use strict';
// define favorite as a non-writable `constant` and give it the value 7
Object.defineProperties(window, {
favorite: {
value: 7,
enumerable: true
}
});
// ^ descriptors are by default false and const are enumerable
var favorite = 7;
// Attempt to overwrite the constant
favorite = 15;
// will still print 7
console.log('my favorite number is still: ' + favorite);
```
The whole code run in browser result in 15, which may be caused by hoisting of 'favorite'. Maybe You can delete
```
var favorite = 7;
```
to fix it.
I guess...