Auto merge of #13508 - tschneidereit:fix-sh-methods-codegen, r=emilio

Fix codegen for iterable's forEach method

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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #13451 (github issue number if applicable).

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The `forEach` method installed on iterable DOM interfaces uses SpiderMonkey's self-hosted implementation of `Array.prototype.forEach`, but it has the wrong value for `nargs`, causing failing asserts in debug and wrong behavior in release builds.

Fixes #13451

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components/script/dom/bindings/codegen/CodegenRust.py

@@ -1605,7 +1605,7 @@ class MethodDefiner(PropertyDefiner):
                 "name": "forEach",
                 "methodInfo": False,
                 "selfHostedName": "ArrayForEach",
-                "length": 0,
+                "length": 1,
                 "condition": PropertyDefiner.getControllingCondition(m,
                                                                      descriptor)
             })