Intent to ship: Imperative Slotting API

[Sean Feng]

Summary: Imperative Slotting API allows a slot element to have manually assigned nodes via the new assign((Element or Text)... nodes) API.





Bug: https://bugzilla.mozilla.org/show_bug.cgi?id=1705141




Standard: https://html.spec.whatwg.org/#dom-slot-assign




Platform coverage: all




Preference: dom.shadowdom.slot.assign.enabled





Other browsers: Chrome has it shipped. Safari also supports it.





Web Platform Tests: https://github.com/web-platform-tests/wpt/tree/master/shadow-dom (imperative-slot-api-* tests)





Thanks,

Sean