fix(orderBy): do not try to call valueOf/toString on `null`

8bfeddb5d671017f4a21b8b46334ac816710b143 added changes to make relational operator work as it
normally would in JS --- unfortunately, this broke due to my failure to account for typeof null
being "object".

This refactoring attempts to convert object values to primitives still, in a fashion similar to
the SortCompare (and subsequently the ToString() algorithm) from ES, in order to account for `null`
and also simplify code to some degree.

BREAKING CHANGE:

Previously, if either value being compared in the orderBy comparator was null or undefined, the
order would not change. Now, this order behaves more like Array.prototype.sort, which by default
pushes `null` behind objects, due to `n` occurring after `[` (the first characters of their
stringified forms) in ASCII / Unicode. If `toString` is customized, or does not exist, the
behaviour is undefined.

Closes #10385
of course, can't rely on IE to behave similarly to other browsers here =( whelp, fixing the tests I guess.