vim-patch:8.0.1459: cannot handle change of directory

Problem:    Cannot handle change of directory.
Solution:   Add the DirChanged autocommand event. (Andy Massimino,
            closes vim/vim#888)  Avoid changing directory for 'autochdir' too often.
https://github.com/vim/vim/commit/b7407d3fc9496f9048fb65ab17b5ba3444965c0e

Only add "auto" pattern. "window" and "global" are already implemented.
Skip `Test_dirchanged_auto` using `CheckFunction test_autochdir`.
Part of PR #15952. More information can be found there.

N/A patches for version.c:

vim-patch:8.0.1460: missing file in patch

Problem:    Missing file in patch.
Solution:   Add changes to missing file.
https://github.com/vim/vim/commit/b5cb65ba2bcc6bbc6d2798a2dea18b95f0b38f5e

vim-patch:8.0.1461: missing another file in patch

Problem:    Missing another file in patch.
Solution:   Add changes to missing file.
https://github.com/vim/vim/commit/15833239a4131279935a4bd574b74fe3a2b0f49f

1 files changed, 2 insertions, 2 deletions

diff --git a/src/nvim/window.c b/src/nvim/window.c
index 1fe4aa1add..a7470889b3 100644
--- a/src/nvim/window.c
+++ b/src/nvim/window.c
@@ -4542,7 +4542,7 @@ static void win_enter_ext(win_T *const wp, const int flags)
     if (os_chdir(new_dir) == 0) {
       if (!p_acd && !strequal(new_dir, cwd)) {
         do_autocmd_dirchanged(new_dir, curwin->w_localdir
-                              ? kCdScopeWindow : kCdScopeTab, true);
+                              ? kCdScopeWindow : kCdScopeTab, kCdCauseWindow);
       }
       shorten_fnames(true);
     }
@@ -4551,7 +4551,7 @@ static void win_enter_ext(win_T *const wp, const int flags)
     // directory: Change to the global directory.
     if (os_chdir((char *)globaldir) == 0) {
       if (!p_acd && !strequal((char *)globaldir, cwd)) {
-        do_autocmd_dirchanged((char *)globaldir, kCdScopeGlobal, true);
+        do_autocmd_dirchanged((char *)globaldir, kCdScopeGlobal, kCdCauseWindow);
       }
     }
     XFREE_CLEAR(globaldir);