Need 'Unspecified' value for KeyboardEvent.code

[garykac]

From @garykac on October 7, 2015 0:26

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'.

Copied from original issue: w3c/uievents#20

[garykac]

From @masayuki-nakano on October 7, 2015 0:51

There are 3 cases of empty code value under current spec:

1. The platform tells UAs a valid scancode or something but proper value for it isn't defined
2. The platform does not tell valid scancode or anything.
3. The key is caused by virtual keyboard or something non-physical keyboard.

It may be impossible to distinguish #2 and #3 if they causes same scancode or something, though. So, only #1 case could cause specific value?

[garykac]

s/Unspecified/Unidentified/