Re: [PATCH v2 0/3] MR5462: Ucrtbase's stderr is now always unbuffered.

[eric pouech (＠epo)]

V2:
- removed code for testing various handle types (only doing file for now) and moved FILE creation to child process
- using position from file descriptor to detect if buffering is enabled
- didn't find any new function in UCRTBASE to distinguish for ucrtbase with buffering of stderr disabled; so ended up using ucrtbase version information (didn't find anything better, if someone has a better idea, feel free to jump in)
- kept the subprocess & reopen because wine/test.h changes stdout buffer state