Error about upstart/systemd when runit

You run Ubuntu 16.04 which has both `upstart` and `systemd` as installed. The `runit` package tries to find out which your system is using, but probably gets confused because two are installed and it picks the wrong one. It can be caused by the idea of "init-system neutrality", expressed under van Smoorenburg `init`, `upstart` and `systemd`.

Logs about `sudo apt-get install git-all`

Setting up runit (2.1.2-3ubuntu1) ...
start: Unable to connect to Upstart: Failed to connect to socket /com/ubuntu/upstart: Connection refused
dpkg: error processing package runit (--configure):
 subprocess installed post-installation script returned error exit status 1
dpkg: dependency problems prevent configuration of git-daemon-run:
 git-daemon-run depends on runit; however:
  Package runit is not configured yet.

dpkg: error processing package git-daemon-run (--configure):
 dependency problems - leaving unconfigured
No apport report written because the error message indicates its a followup error from a previous failure.
                      Errors were encountered while processing:
 runit
 git-daemon-run
E: Sub-process /usr/bin/dpkg returned an error code (1)

%%% logs end %%%

The upstart's start command fails to work. The post-installation maintainer script for runit tries to detect the presence of upstart and start the `runsvdir` upstart job if upstart is present. It does the same with systemd and `runit.servide`.

A thread about the issue here http://unix.stackexchange.com/q/284249/16920
There is a beginning of the solution but no complete resolution. Please, see JdeBP's proposal.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: runit 2.1.2-3ubuntu1
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
Architecture: amd64
CurrentDesktop: Unity
Date: Fri May 20 23:26:48 2016
Dependencies:
 fgetty 0.7-1
 gcc-6-base 6.0.1-0ubuntu1
 libc6 2.23-0ubuntu3
 libgcc1 1:6.0.1-0ubuntu1
InstallationDate: Installed on 2016-05-19 (1 days ago)
InstallationMedia: Ubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1)
SourcePackage: runit
UpgradeStatus: No upgrade log present (probably fresh install)