bf3ef26713
This commit adjusts polymorphization's handling of predicates so that after ensuring that `T` is used in `I: Foo<T>` if `I` is used, it now ensures that `I` is used if `T` is used in `I: Foo<T>`. This is necessary to mark generic parameters that only exist in impl parameters as used - thereby avoiding symbol clashes when using the new mangling scheme. Signed-off-by: David Wood <david@davidtw.co>