The original “Skia” was the development name for QuickDraw GX[1]. (I don’t know why the Wikipedia page doesn’t say that any more.) Cary Clark, who now works at said “elusive Google engineering office”, was the mastermind behind that Skia. TrueType was a sibling project; we (QuickDraw GX team) collaborated closely with them.
Mike’s AlphaMask (sold to OpenWave) didn’t share code with the original Skia but was kind of a Skia 2, with more flexible and clearer architecture than the original. This Skia—which, again, doesn’t share code with either of its predecessors—is a kind of version 3, with a tribute name back to that original Skia.