Normative: Don't output "fractionalDigits" when the value is undefined

[anba]

For consistency with other Intl objects, don't output "fractionalDigits" when its value is undefined.

Applies on top #166.

[anba]

This was previously mentioned in https://github.com/tc39/proposal-intl-duration-format/pull/150#issuecomment-1576233180.

[ben-allen]

There's recent consensus for treating undefined fractionalDigits as meaning "as many fractional digits as needed"

https://github.com/tc39/proposal-intl-duration-format/issues/144#issuecomment-1499823791

[anba]

There's recent consensus for treating undefined fractionalDigits as meaning "as many fractional digits as needed"

This isn't changed with this PR. Only the resolvedOptions output is changed from fractionalDigits: undefined to not emitting a fractionalDigits property at all.

[FrankYFTang]

This PR contains way too many editorial changes. Could we split that?

[anba]

This PR contains way too many editorial changes. Could we split that?

As mentioned above, this PR applies on top of #166. When #166 gets merged, this PR will consist of only a single commit.

[sffc]

TG2 discussion and approval on the normative change: https://github.com/tc39/ecma402/blob/master/meetings/notes-2023-09-07.md#normative-dont-output-fractionaldigits-when-the-value-is-undefined-167

[FrankYFTang]

test PR https://github.com/tc39/test262/pull/3912

[FrankYFTang]

@ben-allen @sffc @ryzokuken This is discussed and agreed in TG2 in 2023-09-07 but we need someone to bring this up to TG1 in Nov 2023 before this can be merged.

[anba]

Rebased now that #166 is merged.

[ryzokuken]

2023-11-28: This PR achieved TC39-TG1 consensus.