[self-interest] twentiethCenturyPlusArgumentCount

[Jecel Assumpcao Jr.]

I think I figured out what was not making sense about the bytecodes. I
had not paid attention and assumed that the instruction sets by index
were

0: twentiethCentury
1: twentiethCenturyPlusArgumentCount

but in fact the vector has a single entry

0: twentiethCenturyPlusArgumentCount

and that is the bytecode set selected when the first bytecode in a
method is 208. There is no way to select the twentiethCentury option
except by starting out with any other opcode than 13.

In fact, it seems to me that twentiethCentury is just another name for
the Self 4.1 bytecodes. If that is the case "bytecodeFormat
instructionSets twentiethCentury opcodes" is wrong and there should not
be a "argumentCount = 13" slot in it. Only the corresponding
twentiethCenturyPlusArgumentCount object should have such a slot. This
is what caused all my confusion.

-- Jecel