Iterates over all properties (not just enumerable ones).

getAllPropertyNames.js

function getAllPropertyNames(obj) {
    var result = [];
    while (obj) {
        // Add the own property names of `obj` to `result`
        Array.prototype.push.apply(result, Object.getOwnPropertyNames(obj));
        obj = Object.getPrototypeOf(obj);
    }
    return result;
}