vim-patch:8.0.1446: acessing freed memory after window command in auto command

Problem:    Acessing freed memory after window command in auto command.
            (gy741)
Solution:   Adjust the pointer in the parent frame. (Christian Brabandt,
            closes vim/vim#2467)
6f361c9912

src/nvim/testdir/test_window_cmd.vim

@@ -455,4 +455,15 @@ func Test_window_contents()
   call test_garbagecollect_now()
 endfunc
 
+func Test_access_freed_mem()
+  " This was accessing freed memory
+  au * 0 vs xxx
+  arg 0
+  argadd
+  all
+  all
+  au!
+  bwipe xxx
+endfunc
+
 " vim: shiftwidth=2 sts=2 expandtab