win32: remove excessive flushing
Our Windows file code was flushing buffers from the operating system
to disk, rather than from the application to the operating system.
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
abort: Permission denied: test-ro-message/b/vehicle