Comment 98 for bug 1252121

For completeness, this is grep -C 5 around PrepareForSleep dbus traffic over a suspend/resume:
         string "Strength"
         variant byte 80
      )
   ]
signal sender=:1.23 -> dest=(null destination) serial=2607 path=/org/freedesktop/UPower; interface=org.freedesktop.UPower; member=Changed
signal sender=:1.3 -> dest=(null destination) serial=677 path=/org/freedesktop/login1; interface=org.freedesktop.login1.Manager; member=PrepareForSleep
   boolean true
signal sender=:1.0 -> dest=(null destination) serial=5501 path=/com/ubuntu/Upstart; interface=com.ubuntu.Upstart0_6; member=EventEmitted
   string "backlight-device-changed"
   array [
      string "KERNEL=acpi_video0"