isOpen has a defaultProp of false, which breaks componentWillReceiveProps's logic

[ckknight]

As per https://github.com/react-native-community/react-native-side-menu/blob/master/index.js#L114,

The first check of typeof props.isOpen !== 'undefined' is always guaranteed to be false, as isOpen cannot be set to undefined, as that is being overridden by defaultProps which coalesces undefined to false.