Fix class properties after nested class' bare super (#7671)

* Fix class properties after nested class' bare super

Fixes #7371.

* Fix node 4 test

* This damn node 4 test

* All of the ClassBody, but not the methods or field inits

* tmp

* tmp

* Use common class environment visitor

* Tests

* Use skipKey to avoid recursive traversal

* Remove old state

* Use jest expect

CONTRIBUTING.md

@@ -197,8 +197,8 @@ In an `exec.js` test, we run or check that the code actually does what it's supp
 
 ```js
 // exec.js
-assert.equal(8, 2 ** 3);
-assert.equal(24, 3 * 2 ** 3);
+expect(2 ** 3).toBe(8);
+expect(3 * 2 ** 3).toBe(24);
 ```
 
 If you need to check for an error that is thrown you can add to the `options.json`