[Bug 26070] user32/class tests show some valgrind warnings

https://bugs.winehq.org/show_bug.cgi?id=26070

--- Comment #3 from Sven  ---
Some leaks were fixed in

2859e7d143d40a5cec330cd6c5b37b919a04a9bc
04847e68f87b26eeef5cbe6a852b1f3914f956e4
470f7b20d468a846f9154450cf2a8000163d5534

The "Conditional jump or move depends on uninitialised value(s)" is tracked in
bug 30827

All other warnings that I found (not definite leaks) are most likely on purpose
and are not supposed to be fixed since there (HINSTANCE)0x12345678 is used as
instance.