Settings: deleteSettings and getSettings reference settingId variable that's never declared

[PN-mruiz]

In order to handle situations where not every parameter is passed in to the deleteSettings and getSettings functions, an attempt is made to determine which parameter is a function, and use that as the callback. trouble is, callback is set to settingId which is a variable that is never declared, so callback will still be undefined by the time we try to use it.