[IndexedDB] Make IDBFactory.cmp [ImplicitThis] (#24)

It would be nice if you could pass `indexedDB.cmp` to `sort()`, e.g.:

```js
var keys = ['a', 4, 3, 1, 2];
keys.sort(indexedDB.cmp); // [1, 2, 3, 4, 'a'] ?
```
... but today you get an "illegal invocation", although `cmp()` is a 'pure' function. Adding `[ImplicitThis]` would allow it.


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Reply to this email directly or view it on GitHub:
https://github.com/w3c/IndexedDB/issues/24