[PATCH] kernel32: Export kernel32's FlushFileBuffers() implementation.

[Marvin]

Hi,

While running your changed tests, I think I found new failures.
Being a bot and all I'm not very good at pattern recognition, so I might be
wrong, but could you please double-check?

Full results can be found at:
https://testbot.winehq.org/JobDetails.pl?Key=64499

Your paranoid android.


=== debian10 (32 bit report) ===

kernel32:
debugger.c:305: Test failed: GetThreadContext failed: 5

=== debian10 (32 bit Chinese:China report) ===

kernel32:
comm.c:918: Test failed: OutQueue should not be empty

=== debian10 (32 bit WoW report) ===

kernel32:
change.c:320: Test failed: should be ready
comm.c:918: Test failed: OutQueue should not be empty
debugger: Timeout