Fix default-directory of buffers visiting files in renamed directories
* lisp/dired-aux.el (dired-rename-file): Take note of whether FILE
is a directory before it is renamed, which makes it impossible to
determine if it was a directory.
(dired-rename-subdir, dired-rename-subdir-1): Revert to using
dired-in-this-tree-p instead of file-in-directory-p, for the
benefit of files that were renamed/removed, because
file-in-directory-p returns nil in those cases. (Bug#54838)