Removing properties with value 0 or false on map

Version: 2.9.2

Example:
```javascript
const r = [1, 0, 3].map(v => ({
x: 0,
y: v
}));
// expected: [ { x: 0, y: 1 }, { x: 0, y: 0 }, { x: 0, y: 3 } ]
// result: [ { y: 1 }, {}, { y: 3 } ]
```

No source file, test, or entry point is named. Start by reproducing the JavaScript snippet in the Firefox debugger and compare the inspected object properties with the expected result; done means values of 0 and false remain visible instead of being removed.

Scritto dal modello di indicizzazione a partire dal testo della issue.