grungey object.isfrozen hack in tv4.js line 118

[kumarperla-gmail]

Please let me know what below code is doing?

// Grungey Object.isFrozen hack
if (!Object.isFrozen) {
Object.isFrozen = function (obj) {
var key = "tv4_test_frozen_key";
while (obj.hasOwnProperty(key)) {
key += Math.random();
}
try {
obj[key] = true;
delete obj[key];
return false;
} catch (e) {
return true;
}
};
}