Remove unnecessary branch

While researching a solution for gh-1881, I started wondering if these two code paths are redundant. Their implementations actually vary in the following ways:

- In the global scope path:
  - the logic is wrapped in the check: `if (typeof predefined[v] !== "boolean") {`
  - list comprehensions are accounted for
- In the function scope path:
  - `funct[v]` is set to `true`

The difference regarding list comprehensions looks more like an oversight than an intentional distinction. I don't understand the other differences well enough to say either way. The fact that the unit tests continue to pass means that either: (1) this is a valid refactoring or (2) there is an issue with code coverage. I'd appreciate the advice of the maintainers to decide which it is.