Possible alternative to rescueLostKitty function

[adamkolar]

Is there a reason why transferral to the address of the ERC721 contract isn't forbidden in the _transfer function instead of solving the problem with the rescueLostKitty function? It's a question of one require, so the added gas cost should be pretty minimal and considering the amount of time and energy needed to coordinate a "rescue mission", it could be worth it.

    /// @dev Transfers a kitty owned by this contract to the specified address.
    ///  Used to rescue lost kitties. (There is no "proper" flow where this contract
    ///  should be the owner of any Kitty. This function exists for us to reassign
    ///  the ownership of Kitties that users may have accidentally sent to our address.)
    /// @param _kittyId - ID of kitty
    /// @param _recipient - Address to send the cat to
    function rescueLostKitty(uint256 _kittyId, address _recipient) public onlyCOO whenNotPaused {
        require(_owns(this, _kittyId));
        _transfer(this, _recipient, _kittyId);
    }

[dete]

Good point, @adamkolar! However, this was already reported in #5. 😁