Revert "Do not crash on unicode filenames"

This reverts commit 8e5131d5ec8d8be91972997620c3b8b73c6b568b.

I pushed a bogus version of this, which somehow lost the kwargs again.
Sync of https://github.com/pantsbuild/pants/commit/9c5e616a547b38b3d303d2a2b74c55b7a186d647