[PATCH] kernel32: Set error if dstlen < 0 in codepage conversion functions.

[Marvin]

Hi,

While running your changed tests on Windows, 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=19138

Your paranoid android.


=== build (build) ===
Could not copy the patch to the VM: the "nc -q0 '10.42.42.130' '4242'" command returned 1