I hope this was an outside project rather than something the foundation itself supported. The grammar of most natural languages cannot usefully be assessed with the rudimentary machine "checking" that's popular and somewhat effective for spelling. Grammar checkers mostly serve to give people who aren't very confident in their use of language a bunch of superstitious beliefs that make their writing awkward and leave them frustrated (e.g. it's common for such checkers to forbid preposition stranding in English even though stranding is sometimes the right choice).
Of course (I assume) this is off by default, but it's one of those features that will sucker in users who'd be better off without it. Those most capable of rejecting bad rules from such a "checker" won't be foolish enough to enable it in the first place.