Hibernation complete fix after upgrading to Ubuntu 14.04 LTS

Lots of issues with Gnome after upgrading Ubuntu GNU/Linux from 12.04 LTS to 14.04 LTS. The fix for most issues is to first login with the Ubuntu (Unity) session before choosing another session.

Anyway, hibernation ceases to be available after the upgrade.

It still works with sudo pm-hibernate thankfully.  The solution is partially out there (but obviously use /etc and not /var/lib for your changes.  This will work only with no other user logged on.  Otherwise the menu option is not available in the indicator applet.  Pressing the power button and running hibernation from there opens up a policy kit authentication window.  Hence, as hinted here, additionally append further changes to /etc/polkit-1/localauthority/50-local.d/com.ubuntu.enable-hibernate.pkla.

[Re-enable hibernate by default in upower]
Identity=unix-user:*
Action=org.freedesktop.upower.hibernate
ResultActive=yes

[Re-enable hibernate by default in logind]
Identity=unix-user:*
Action=org.freedesktop.login1.hibernate
ResultActive=yes

Identity=unix-user:*
Action=org.freedesktop.login1.hibernate-multiple-sessions
ResultActive=yes

That's it. You do not have to kill or restart anything. You do not need to install the hibernate or uswsusp packages.

Update: sometimes the network manager becomes disabled after resuming from hibernation. I created the executable script /etc/pm/sleep.d/55_local_networkmanager to solve this.

#!/bin/sh
# http://www.smallbulb.net/2014/640-xubuntu-upgrade-to-13-10-with-troubles
# This script gets NetworkManager out of suspend.
case $1 in
    suspend|suspend_hybrid|hibernate)
        # No need to do anything here.
        ;;
    resume|thaw)
        #nmcli nm sleep false
        if [ "`nmcli -f state -t nm`" = "asleep" ]; then
          service network-manager restart
        fi
        ;;
esac