[IndexedDB] Keypath evaluation steps yield a value, not a key (#4)

The steps to extract/evaluate a key path yield a value, rather than going one step further and converting the result to a key.

This complicates the steps because a temporary Array is created if the input is an array.

The reason the steps are written this way is that after the extraction is done, the value can be converted to a key in one of two different ways - the "normal" case or the "multiEntry" case (which ignores bad values and drops duplicates).

This adds complication throughout the spec, so it should be refactored somehow.

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/IndexedDB/issues/4