[WebXR] Add a new enum type to represent session features
Currently the implementation only supports ReferenceSpaceTypes as possible session features. Add a new enum type to represent session features, and includes "hand-tracking" in session feature parsing.
Created attachment 456763 [details]
Committed r292449 (249300@main): <https://commits.webkit.org/249300@main>
All reviewed patches have been landed. Closing bug and clearing flags on attachment 456763 [details].