user32: For an owner-drawn listbox without strings WM_MEASUREITEM still needs correct itemData.

dlls/user32/listbox.c

@@ -1554,7 +1554,7 @@ static LRESULT LISTBOX_InsertItem( LB_DESCR *descr, INT index,
         mis.CtlType    = ODT_LISTBOX;
         mis.CtlID      = id;
         mis.itemID     = index;
-        mis.itemData   = data;
+        mis.itemData   = str ? (ULONG_PTR)str : data;
         mis.itemHeight = descr->item_height;
         SendMessageW( descr->owner, WM_MEASUREITEM, id, (LPARAM)&mis );
         item->height = mis.itemHeight ? mis.itemHeight : 1;

dlls/user32/tests/msg.c

@@ -14387,7 +14387,7 @@ static void test_listbox_messages(void)
     ret = SendMessageA(listbox, LB_ADDSTRING, 0, (LPARAM)"item 2");
     ok(ret == 2, "expected 2, got %ld\n", ret);
 
-    ok_sequence(wm_lb_addstring_sort_ownerdraw, "LB_ADDSTRING", TRUE);
+    ok_sequence(wm_lb_addstring_sort_ownerdraw, "LB_ADDSTRING", FALSE);
     check_lb_state(listbox, 3, LB_ERR, 0, 0);
 
     log_all_parent_messages--;