Provide a stub implementation of umask that is enough to get some tests passing.
More work is needed upstream in Emscripten to make all umask tests to pass.
(cherry picked from commit 12e52cad71)
Co-authored-by: Hood Chatham <roberthoodchatham@gmail.com>
Corrects the handling of getuid on emscripten, which was consistently reporting as 0.
(cherry picked from commit e81c4e84b3)
Co-authored-by: Hood Chatham <roberthoodchatham@gmail.com>