Allow |, &, and ^ operators to have null/undefined inputs

[ghost]

Fixes #22230
Would make #22088 simpler

[sandersn]

The change looks good and I think the usages this enables are fine too. I'd like another reviewer to sign off before merging, just so we get two people thinking about unintended consequences.

[weswigham]

I like this change, ofc. @rbuckton you're a real fan of the undefined-is-implicitly-bitwise-zero pattern; you agree with this?

[RyanCavanaugh]

TIL

I'm hesitant on this because (a) you could just use ! and (b) this reasoning applies equally to e.g. "foo" | 0 (which is 0). If the logic is "It doesn't return NaN" then [3] | { } should be legal too, because the binary bitwise operators always return an int. I'm strawmanning of course, but what about e.g. string | number as an operand? Probably most codebases with a flag value would treat null/undefined as 0 but I'm not convinced that it's all of them.

[weswigham]

Ofc, the reason we want it is because we use the fact that null/undefined are effectively zero in bitwise ops extensively inside our codebase. Tbqh, I think the question to ask, is how often does forcing you to handle null/undefined explicitly here find an error, versus just forcing you to write (and slowly become blind to) nonnull assertions.

[ghost]

Note: "1" | 2 is 3, as is ({ toString() { return "1" } }) | 2, so not a good idea to rely on anything else being treated as 0.

[typescript-bot]

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