Proposal: https://github.com/tc39/proposal-regexp-unicode-property-escapes

These tests have been generated by the script at https://github.com/mathiasbynens/unicode-property-escapes-tests. They check all the properties and values that should be supported by implementations against the symbols they’re supposed to match. False positives are detected as well.

Ref. #950.
Ref. https://github.com/tc39/proposal-regexp-unicode-property-escapes/issues/4.