[JSC] AsyncFromSyncIterator should close its sync-iterator when throw is null or undefined - #39876

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[JSC] `AsyncFromSyncIterator` should close its sync-iterator when `throw` is null or undefined
https://bugs.webkit.org/show_bug.cgi?id=286885

Reviewed by Yusuke Suzuki.

The normative change for `AsyncFromSyncIterator`[1] includes the following two changes:

1. AsyncFromSyncIterator now closes the sync iterator when `throw` is called on the
wrapper but is not implemented on the sync iterator. In that case, it updates the
rejection value to a `TypeError` to reflect the contract violation.
2. AsyncFromSyncIterator closes its sync iterator when the sync iterator yields a
rejected promise as its value.

This normative change has already been implemented in V8[2]. This patch changes to
implement only the first change.

[1]: tc39/ecma262#2600
[2]: v8/v8@6c3f7aa#diff-c18e5d5743326f6ba544801f6ce25154b785f759885651f98924d5b56dc1c2e6

* JSTests/stress/async-from-sync-iterator-prototype-throw-close-sync-iter.js: Added.
(shouldBe):
(shouldThrowAsync):
(throw.new.Error.const.syncIterator.get throw):
(throw.new.Error.const.asyncIterator):
(throw.new.Error.async OurError):
(throw.new.Error):
(const.syncIterator.get throw):
(throw.new.Error.async drainMicrotasks):
(const.asyncIterator):
(async OurError):
(OurError):
(NotOurError):
(const.syncIterator.get return):
(async drainMicrotasks):
(async asyncIterator):
* JSTests/test262/expectations.yaml:
* Source/JavaScriptCore/builtins/AsyncFromSyncIteratorPrototype.js:
(throw):

Canonical link: https://commits.webkit.org/289726@main

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