PlaceVOffsetT prepends a VOffsetT to the Builder, without checking
        for space.

def PlaceVOffsetT(self, x):
        """PlaceVOffsetT prepends a VOffsetT to the Builder, without checking
        for space.
        """
        N.enforce_number(x, N.VOffsetTFlags)
        self.head = self.head - N.VOffsetTFlags.bytewidth
        encode.Write(packer.voffset, self.Bytes, self.Head(), x)