WiFi does not work after about 1 in 4 suspends

[Phill]

Steps: Suspend, wait, resume, a few times.

The Network Manager applet shows WiFi is enabled and shows just one or a handful of WiFi names, they don't include some that are known to be available and in use on other computers.

Disabling and enabling WiFi does not fix the problem.

Disabling and enabling networking does not fix the problem.

Adding the following does not help:
/etc/pm/config.d/unload_modules
SUSPEND_MODULES="$SUSPEND_MODULES iwlwifi"

Running `sudo wpa_cli scan` does not restore the network connection. I only mention this because of a similar bug where this is an effective workaround.

Only workaround which works perfectly and instantly is to run:
sudo service network-manager restart

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: network-manager 1.2.0-0ubuntu0.16.04.2
ProcVersionSignature: Ubuntu 4.4.0-22.40-generic 4.4.8
Uname: Linux 4.4.0-22-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.1
Architecture: amd64
CurrentDesktop: Unity
Date: Sat Jun 4 18:18:50 2016
IfupdownConfig:
 # interfaces(5) file used by ifup(8) and ifdown(8)
 auto lo
 iface lo inet loopback
InstallationDate: Installed on 2016-05-30 (4 days ago)
InstallationMedia: Ubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1)
IpRoute:
 default via 192.168.43.1 dev wlp2s0 proto static metric 600
 169.254.0.0/16 dev wlp2s0 scope link metric 1000
 192.168.43.0/24 dev wlp2s0 proto kernel scope link src 192.168.43.89 metric 600
NetworkManager.state:
 [main]
 NetworkingEnabled=true
 WirelessEnabled=true
 WWANEnabled=true
SourcePackage: network-manager
UpgradeStatus: No upgrade log present (probably fresh install)
nmcli-dev:
 DEVICE TYPE STATE DBUS-PATH CONNECTION CON-UUID CON-PATH
 wlp2s0 wifi connected /org/freedesktop/NetworkManager/Devices/0 HTC Portable Hotspot DF99 c29b59ba-b6ef-49db-b159-75ec21d3f436 /org/freedesktop/NetworkManager/ActiveConnection/0
 enp1s0 ethernet unavailable /org/freedesktop/NetworkManager/Devices/1 -- -- --
 lo loopback unmanaged /org/freedesktop/NetworkManager/Devices/2 -- -- --
nmcli-nm: Error: command ['nmcli', '-f', 'all', 'nm'] failed with exit code 2: Error: Object 'nm' is unknown, try 'nmcli help'.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Phill (phill.l)]

Maybe not a duplicate of 1576747 as I have no network communication on resume. The description of 1576747 states "Oddly enough, I'm still able to communicate on the network that I was connected to prior to suspend".

[Phill (phill.l)]

Probably not a duplicate of #1585863 because that bug says that the network can be restored by performing `sudo wpa_cli scan`. I just tried this and it does not work for me, only `sudo service network-manager restart` seems to work as indicated in the bug description.