[PATCH] comctl32/tests: Avoid an unneeded lstrlenW() call.

[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=58105

Your paranoid android.


=== wvistau64_fr (32 bit report) ===

comctl32:
button.c:825: Test failed: BM_SETSTATE/TRUE on a button: the msg sequence is not complete: expected 0000 - actual 000f