Previously, UMD/CommonJS class inline declarations of the form:
```ts
exports.Foo = (function() { function Foo(); return Foo; })();
```
were capturing the whole IIFE as the implementation, rather than
the inner class (i.e. `function Foo() {}` in this case). This caused
the interpreter to break when it was trying to access such an export,
since it would try to evaluate the IIFE rather than treating it as a class
declaration.
PR Close#39346
413b55273b