Define clearly how the capture IDL attribute is reflected

[foolip]

https://w3c.github.io/html-media-capture/#the-capture-attribute says "The capture IDL attribute must reflect the respective content attribute of the same name." and links to https://html.spec.whatwg.org/multipage/infrastructure.html#reflect

However, the bit in HTML that defined how to reflect an enum was removed in whatwg/html#2585. Probably the solution is to make the IDL attribute a DOMString, and handling it similarly to for example https://html.spec.whatwg.org/multipage/embedded-content.html#attr-track-kind

@annevk @domenic

[domenic]

Agreed. You could also do what we've been doing for other cases that avoids such a table, such as

Each referrer policy, including the empty string, is a keyword for this attribute, mapping to a state of the same name.

or

Each request destination, including the empty string, is a keyword for this attribute, mapping to a state of the same name.

The important thing though is to update all specs to refer to the state of the attribute, not the value, since e.g. the value could be "asdf", but the state will be whatever you've set the invalid value default to.