Duplicated name in class static block should be normal but throws SyntaxError

[Kanguk Lee]

// input.js
class x { static { var x ; } }
________________________________

Hello,

Executing the input.js using JSC throws SyntaxError, but it is expected to terminate normally.

Running the input.js with JSC gives

---
$ jsc input.js
Exception: SyntaxError: Cannot declare a var variable that shadows a let/const/class variable: 'x'.
at input.js:1
---

while other engines behave like

---
# V8
$ node input.js
// no error

# GraalJS
$ js input.js
// no error
---


WebKit version: 615.1.10

[Radar WebKit Bug Importer]

<rdar://problem/101940195>

[Yijia Huang]

Pull request: https://github.com/WebKit/WebKit/pull/6126

[EWS]

Committed 256311@main (d102e7a7748f): <https://commits.webkit.org/256311@main>

Reviewed commits have been landed. Closing PR #6126 and removing active labels.