function _safeWrap(obj, name, methods, wrapper) {
  if (methods && methods.length) {
    shimmer.wrapMethod(obj, name, methods, wrapper)
  }
}
Performs a `wrapMethod` if and only if `methods` is truthy and has a length
greater than zero.

@param {object}        obj     - The source of the methods to wrap.
@param {string}        name    - The name of this source.
@param {string | Array}  methods - The names of the methods to wrap.
@param {Function}      wrapper - The function which wraps the methods.