mate-session does not honor systemd-inhibit

[Mikko Rantalainen]

mate-session ignores any inhibit values set via systemd-inhibit and honors only settings done via mate-session-inhibit. This should be fixed because Ubuntu 18.04 is trying to inhibit things via systemd-inhibit and mate-session may end up suspending the system even if systemd-inhibit is requesting no suspend.

Test case:

$ systemd-inhibit --why=TEST --what=sleep --mode=block sleep 10m

Select "Suspend" from mate menu.

Actual result:

System suspends (S3 sleep).

Expected result:

System turns off the screen and delays the suspend for 10 minutes OR a dialog pops up that says that sleep is currently blocked with buttons "Cancel", "Sleep when possible" and "Force sleep now". The "Sleep when possible" option should wait until sleep is no longer inhibited.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: mate-session-manager 1.20.0-1
ProcVersionSignature: Ubuntu 4.18.0-25.26~18.04.1-lowlatency 4.18.20
Uname: Linux 4.18.0-25-lowlatency x86_64
ApportVersion: 2.20.9-0ubuntu7.6
Architecture: amd64
CurrentDesktop: MATE
Date: Tue Jul 2 18:52:43 2019
EcryptfsInUse: Yes
InstallationDate: Installed on 2019-01-05 (177 days ago)
InstallationMedia: Ubuntu 18.04.1 LTS "Bionic Beaver" - Release amd64 (20180725)
SourcePackage: mate-session-manager
UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

[Expired for mate-session-manager (Ubuntu) because there has been no activity for 60 days.]