Object.fromEntries: use verifyProperty; add specification details

test/built-ins/Object/fromEntries/empty-iterable.js

test/built-ins/Object/fromEntries/evaluation-order.js

...-ins/Object/fromEntries/iterator-closed-for-null-entry.js

...ns/Object/fromEntries/iterator-closed-for-string-entry.js

...ntries/iterator-closed-for-throwing-entry-key-accessor.js

...ntries/iterator-closed-for-throwing-entry-key-tostring.js

...ries/iterator-closed-for-throwing-entry-value-accessor.js

...ries/iterator-not-closed-for-next-returning-non-object.js

...Entries/iterator-not-closed-for-throwing-done-accessor.js

...ject/fromEntries/iterator-not-closed-for-throwing-next.js

...ct/fromEntries/iterator-not-closed-for-uncallable-next.js

test/built-ins/Object/fromEntries/length.js

test/built-ins/Object/fromEntries/name.js

test/built-ins/Object/fromEntries/requires-argument.js

test/built-ins/Object/fromEntries/simple-properties.js

...Object/fromEntries/string-entry-string-object-succeeds.js