array_key_exists with float keys (bug #60039)

Hi internals! I'd like to get some attention to bug #60039 [1]. It is about the behavior of array_key_exists with "unusual" keys like floats, bools and resources. Currently array_key_exists throws a warning if such a key is passed. isset() on the other hand (and native array accesses in general) treat them as valid keys, with floats being converted to ints and bools and resources treated just like ints. I would like to see array_key_exists behave consistent with isset($array[$key]) / $array[$key]. The bug has a patch attached that does this. I don't think that this change has any BC impact as it only *removes* warnings. Nikita [1]: https://bugs.php.net/bug.php?id=60039