[Bug 36636] valgrind shows an uninitialized write in shell32/tests/ appbar.c

https://bugs.winehq.org/show_bug.cgi?id=36636

--- Comment #11 from Austin English  ---
Still in 4.0-rc3:
==20528== Syscall param writev(vector[...]) points to uninitialised byte(s)
==20528==    at 0x43567D3: writev (writev.c:26)
==20528==    by 0x7BC75457: send_request (server.c:228)
==20528==    by 0x7BC76158: server_call_unlocked (server.c:288)
==20528==    by 0x7BC761AD: wine_server_call (server.c:321)
==20528==    by 0x56A5D81: put_message_in_queue (message.c:3161)
==20528==    by 0x56A36E7: send_inter_thread_message (message.c:3229)
==20528==    by 0x56A39CA: send_message (message.c:3305)
==20528==    by 0x56A3AFD: SendMessageTimeoutW (message.c:3449)
==20528==    by 0x4C2FCAB: SHAppBarMessage (appbar.c:142)
==20528==    by 0x4A7E458: test_setpos (appbar.c:222)
==20528==    by 0x4A7F3F7: func_appbar (appbar.c:447)
==20528==    by 0x4AD1E90: run_test (test.h:617)
==20528==    by 0x4AD28CE: main (test.h:701)
==20528==  Address 0x4c0fc68 is on thread 1's stack
==20528==  in frame #8, created by SHAppBarMessage (appbar.c:65)
==20528==  Uninitialised value was created by a stack allocation
==20528==    at 0x4A7E39B: test_setpos (appbar.c:203)
==20528==