bug#39171: 27.0.60; tramp: async-shell-command annoying scrolling

[Tino Calancha]

X-Debbugs-Cc: Michael Albinus <michael.albinus@gmx.de>

emacs -Q
;; I visit /tmp
C-x d /sudo::/tmp RET
;; prompted for pasword as usual; then I got my Dired buffer
M-& date RET
;; Prompted for password (see Bug#39170)
;; once I put my password, the command executes and it shows
;; weird scrolling at *Async Shell Command*: the output at line 1
;; is not visible because the window shows the buffer from line 2
;; Same with each command regardless of output size: you cannot see
;; the output until you scroll up 'by hand'.

Git bisect suggests that the issue arose with commit:
'Support history files in remote shells (Bug#36742)'
(7f95d2d40726b4fb4a2ba1b8c373f3498e286d34)


In GNU Emacs 27.0.60 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.5)
 of 2020-01-18 built on calancha-pc.dy.bbexcite.jp
Repository revision: 4217bc229b8d1614b3b5c44fd1dadb775ed1ef4a
Repository branch: emacs-27
Windowing system distributor 'The X.Org Foundation', version 11.0.12004000
System Description: Debian GNU/Linux 10 (buster)