bug#53524: 27.2; No error for creation of Dired listing with nonexistent files/dirs

[Drew Adams <drew.adams@oracle.com>]

Bug #18836 was fixed in a minimal way: just raising an error for a
nonexistent file or directory when you try to create a Dired buffer
listing that contains it.

As mentioned in that bug report, it would be more user-friendly and more
useful to let you create the Dired buffer, and raise the error only
if/when you later try to access the file or directory, if it still does
not exist.  Better yet (if it still doesn't exist) is to ask if you want
to create it then, instead of just raising an error.

IOW, late binding, please.  There's no reason to just error out because
a single file or dir in the requested listing doesn't exist yet.  You
should be able to create the listing, and later (with or without Dired)
create the missing file or dir.

As stated in bug #18836:

  Let user attempts to actually access it raise an error, and let
  no error be raised if the file is created after creating the
  Dired buffer but before the user tries to access the file.

In GNU Emacs 27.2 (build 1, x86_64-w64-mingw32)
 of 2021-03-26 built on CIRROCUMULUS
Repository revision: deef5efafb70f4b171265b896505b92b6eef24e6
Repository branch: HEAD
Windowing system distributor 'Microsoft Corp.', version 10.0.19043
System Description: Microsoft Windows 10 Pro (v10.0.2009.19043.1466)