Update parseInt parameter name and jsdoc

[sangxxh]

Fixes #42741

First contribution.

Update param name and docstring for parseInt to be more readable/consistent.

[DanielRosenwasser]

Looks like the docs affect some tests. Run

gulp runtests
gulp baseline-accept
git add tests
git commit -m "Accepted baselines."
git push

[sangxxh]

Thanks @DanielRosenwasser