[GR-28240] New Set Methods proposal.

PullRequest: js/1976

Author: wirthi

CHANGELOG.md

@@ -6,6 +6,7 @@ The main focus is on user-observable behavior of the engine.
 ## Version 21.2.0
 * Graal.js now prints a warning when runtime compilation is not supported. This warning can be disabled using the '--engine.WarnInterpreterOnly=false' option or the '-Dpolyglot.engine.WarnInterpreterOnly=false' system property.
 * Added the `js.unhandled-rejections` option to track unhandled promise rejections in a polyglot `Context`. By default, the option is set to `none`, and unhandled promise rejections are not tracked.
+* Implemented the [New Set Methods](https://github.com/tc39/proposal-set-methods) proposal. It is available behind an experimental flag (`--js.new-set-methods`).
 
 ## Version 21.1.0
 * Updated Node.js to version 14.16.1.