This will substitute non-commonizable classifiers with known
type-aliases (which might be commonizable).
A simple example depending on this substitution comes from posix:
Most function and properties use the `FILE` typealias which
is available across all platforms.
Some linux platforms use `__IO_FILE` in their signature, which
is just linux specific. This type substitution will figure out, that
this type can be substituted with `FILE`.
^KT-47433 Verification Pending
sebastian.sellmair
7c450f9884