comctl32/tests: Use initialized window handle when rebuilding toolbar (Coverity)

[Frédéric Delanoy]

Initializing to NULL so rebuild_toolbar doesn't read uninited data

CID 5566
---
 dlls/comctl32/tests/toolbar.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/dlls/comctl32/tests/toolbar.c b/dlls/comctl32/tests/toolbar.c
index 474e5ef..2444975 100644
--- a/dlls/comctl32/tests/toolbar.c
+++ b/dlls/comctl32/tests/toolbar.c
@@ -1881,7 +1881,7 @@ static void test_TB_GET_SET_EXTENDEDSTYLE(void)
 {
     DWORD style, oldstyle, oldstyle2;
     const extended_style_t *ptr;
-    HWND hwnd;
+    HWND hwnd = NULL;
     int i;
 
     rebuild_toolbar(&hwnd);
-- 
1.7.9