Improve super.x output

[liuxingbaoyu]

Q	A
Fixed Issues?	Fixes #1, Fixes #2
Patch: Bug Fix?
Major: Breaking Change?
Minor: New Feature?
Tests Added + Pass?	Yes
Documentation PR Link
Any Dependency Changes?
License	MIT

I personally don't like having to call getPrototypeOf every time because it's slow, but we have a test that relies on this behavior.

[babel-bot]

Build successful! You can test your changes in the REPL here: https://babeljs.io/repl/build/57350

[nicolo-ribaudo]

Finally reviewing this, sorry it took so long.

I personally don't like having to call getPrototypeOf every time because it's slow, but we have a test that relies on this behavior.

This is covered by the constantSuper assumption, right?

---

Can you add a test for the execution order between property access and arguments evaluation?

let argsEval = false;
let err = {};

class A {
  get x() { throw {} }
}

class B extends A {
  method() {
    super.x(argsEval = true);
  }
}

expect(() => new B().method()).toThrow(err);
expect(argsEval).toBe(false);