[uievents] Need 'Unspecified' value for KeyboardEvent.code (#20)

The current spec doesn't define an 'Unspecified' value that can be used when the code value cannot be determined.

Having a separate value is important to be able to distinguish between 'not implemented' and 'implemented, but unable to determine code'.

Currently, we define 'Unspecified' for 'key', but don't have the equivalent text for 'code'.


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Reply to this email directly or view it on GitHub:
https://github.com/w3c/uievents/issues/20