fix listview trace crash

[Rein Klazes <rklazes@xs4all.nl>]

Hi,

With these fixes the original reason to debug disappeared as well ;-)

    dlls/comctl32/	: listview.c
    Fix some crashes running with --debugmsg +listview

Rein.
-- 
Rein Klazes
rklazes@xs4all.nl
--- wine/dlls/comctl32/listview.c	2002-09-19 09:06:24.000000000 +0200
+++ mywine/dlls/comctl32/listview.c	2002-09-20 21:19:41.000000000 +0200
@@ -337,7 +337,8 @@
 	wstr = HeapAlloc(GetProcessHeap(), 0, len * sizeof(WCHAR));
 	if (wstr) MultiByteToWideChar(CP_ACP, 0, (LPCSTR)text, -1, wstr, len);
     }
-    TRACE("   wstr=%s\n", debugstr_w(wstr));
+    TRACE("   wstr=%s\n", text == LPSTR_TEXTCALLBACKW ?
+            "(callback)" : debugstr_w(wstr));
     return wstr;
 }
 
@@ -604,6 +605,7 @@
     LVITEMW item;
     BOOL bReturn;
 
+    ZeroMemory(&item, sizeof(item));
     item.iItem = iItem;
     item.mask = LVIF_PARAM;
     LISTVIEW_GetItemT(infoPtr, &item, TRUE, TRUE);
@@ -1938,6 +1940,7 @@
 static void LISTVIEW_SetSelection(LISTVIEW_INFO *infoPtr, INT nItem)
 {
     LVITEMW lvItem;
+    ZeroMemory(&lvItem, sizeof(lvItem));
 
     LISTVIEW_RemoveAllSelections(infoPtr);
 
@@ -4995,6 +4998,7 @@
          * the text in the specified font.
          */
         LVITEMW lvItem;
+        ZeroMemory(&lvItem, sizeof(lvItem));
         lvItem.mask = LVIF_TEXT;
         lvItem.iItem = nItem;
         lvItem.iSubItem = 0;