[PATCH] user32: check GetClipboardFormatName length

[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=33944

Your paranoid android.


=== w8 (32 bit clipboard) ===
clipboard.c:402: Test failed: GlobalGetAtomNameA should fail
clipboard.c:403: Test failed: err -559038737