According to [this](https://github.com/w3c/webappsec-permissions-policy/blob/main/permissions-policy-explainer.md#appendix-big-changes-since-this-was-called-feature-policy), it should not accept `'`, only `"` as enclosing character. It should produce a "We didn't detect a viable policy." error. Check this at "payment" feature declaration: Incorrect: <img width="1208" alt="pp_notok2" src="https://user-images.githubusercontent.com/7722456/117364059-bc87cb00-aebd-11eb-901e-b2f60c33bda8.png"> Correct: <img width="1223" alt="pp_ok" src="https://user-images.githubusercontent.com/7722456/117364086-c3164280-aebd-11eb-9960-99fcf9818cf8.png">
