Properly transpile exported classes that shadowed builtins

[JLHwung]

Q	A
Fixed Issues?	Fixes #15293
Patch: Bug Fix?	Yes
Major: Breaking Change?
Minor: New Feature?
Tests Added + Pass?	Yes
Documentation PR Link
Any Dependency Changes?
License	MIT

This is a hotfix for #15293. See below for the root cause analysis.

In the future we should revisit how and when the helpers are injected.

[babel-bot]

Build successful! You can test your changes in the REPL here: https://babeljs.io/repl/build/53694/

[nicolo-ribaudo]

See below for the root cause analysis.

Below where? 😅

EDIT: Found it, it's a comment in the code.

[nicolo-ribaudo]

Fwiw, I'm working on a @babel/parser,/@babel/traverse/@babel/generator RFC to track bindings using an UID instead of their name, so that even if there are conflicts (e.g. Number in the class name and in the helper), our logic will still be able to distinguish them (because they would have different UIDs) and we only need to rename one while printing to prevent the generated JS code from having the same conflict.

[liuxingbaoyu]

It's annoying that parent and parentNode are different.