Fix JsBackedMap sometimes returning undefined instead of null#396

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jsbackedmap-undefined

Commits on May 31, 2024

Add regression tests for JsBackedMap returning undefined
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Fix JsBackedMap sometimes returning undefined instead of null
greglittlefield-wf
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Commits on Jun 20, 2024

Do `?? null` before passing the value into unwrapIfNeeded
greglittlefield-wf
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