bug#20000: 25.0.50; auto-revert tries to install notification handler on remote files

[Filipp Gunbin <fgunbin@fastmail.fm>]

On 04/03/2015 15:32 +0100, Michael Albinus wrote:

> Filipp Gunbin <fgunbin@fastmail.fm> writes:
>
> Hi Filipp,
>
>> I ran across this in this way:
>>
>> 1) open remote file via tramp and ssh
>> 2) turn on global-auto-revert-mode
>>
>> Tramp then asked for the password for the remote host.
>
> Have you set auto-revert-remote-files to nil? Otherwise, it would be the
> expected behaviour.

Of course, it is nil.

In fact, `auto-revert-remote-files' is checked only in
`auto-revert-handler' (and that function is called from the notification
handler when notification is triggered).

Notification handler is called before `auto-revert-handler':

		(when (auto-revert-active-p)
		  ;; Enable file notification.
		  (when (and auto-revert-use-notify
			     (not auto-revert-notify-watch-descriptor))
		    (auto-revert-notify-add-watch))
		  (auto-revert-handler)))


As I see, there are two kinds of revert prevention for remote files:

1) For files matching `auto-revert-notify-exclude-dir-regexp' the
notification handler is not set all (but is set anyway and my patch
fixes it).

2) If we still get into `auto-revert-handler' in a remote file (like
when we called `global-auto-revert-mode' and it called
'auto-revert-handler') then the `auto-revert-remote-files' will prevent
the actual revert.

This fix applies only to notification handler installation, other
functionality seems to work right.

Filipp