xorg package removed when installing plainbox-provider-sru

[Pierre Equoy]

plainbox-provider-sru version: 1.17.0~ppa~ubuntu18.04.1

Steps
On a fresh 18.04 install, run the following commands:

sudo add-apt-repository ppa:hardware-certification/public
sudo apt update
sudo apt-get install checkbox-ng plainbox-provider-resource-generic plainbox-provider-certification-client plainbox-provider-checkbox canonical-certification-client

Check the status of xorg package:

$ apt-cache policy xorg
xorg:
  Installed: 1:7.7+19ubuntu7.1
(...)

Try to install plainbox-provider-sru:

--------------------------------------------------------------------------------
$ sudo apt install plainbox-provider-sru
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
  apt-clone archdetect-deb btrfs-tools dmraid gir1.2-timezonemap-1.0 gir1.2-xkl-1.0 kpartx kpartx-boot libdebian-installer4 libdmraid1.0.0.rc16 libglu1-mesa libido3-0.1-0 libtimezonemap-data
  libtimezonemap1 libxatracker2 python3-icu python3-pam rdate x11-apps x11-session-utils xbitmaps xinit xserver-xorg-input-all-hwe-18.04 xserver-xorg-input-libinput-hwe-18.04
  xserver-xorg-input-wacom-hwe-18.04 xserver-xorg-video-all-hwe-18.04 xserver-xorg-video-amdgpu-hwe-18.04 xserver-xorg-video-ati-hwe-18.04 xserver-xorg-video-fbdev-hwe-18.04
  xserver-xorg-video-intel-hwe-18.04 xserver-xorg-video-nouveau-hwe-18.04 xserver-xorg-video-qxl-hwe-18.04 xserver-xorg-video-radeon-hwe-18.04 xserver-xorg-video-vesa-hwe-18.04
  xserver-xorg-video-vmware-hwe-18.04
Use 'sudo apt autoremove' to remove them.
The following additional packages will be installed:
  apt-file autoconf automake autotools-dev build-essential checkbox-provider-phoronix cmake cmake-data g++ g++-7 git git-man libc-dev-bin libc6-dev libcapnp-0.6.1 libcurl4-openssl-dev libdmx-dev libdmx1
  libdrm-amdgpu1 libdrm-common libdrm-dev libdrm-intel1 libdrm-nouveau2 libdrm-radeon1 libdrm2 liberror-perl libexpat1-dev libfontconfig1-dev libfontenc-dev libfreetype6-dev libfs-dev libfs6 libgmp-dev
  libgmp3-dev libgmpxx4ldbl libice-dev libjsoncpp1 libmirclient-dev libmirclient9 libmircommon-dev libmircommon7 libmircookie-dev libmircookie2 libmircore-dev libmircore1 libmirprotobuf3
  libpciaccess-dev libpixman-1-dev libpng-dev libpng-tools libprotobuf-dev libprotobuf-lite10 libpthread-stubs0-dev libregexp-assemble-perl librhash0 libsigsegv2 libsm-dev libssl-dev libstdc++-7-dev
  libuv1 libvulkan-dev libvulkan1 libx11-dev libx11-doc libxau-dev libxaw7-dev libxcb1-dev libxcomposite-dev libxcursor-dev libxdamage-dev libxdmcp-dev libxext-dev libxfixes-dev libxfont-dev libxft-dev
  libxi-dev libxinerama-dev libxkbcommon-dev libxkbcommon-x11-0 libxkbcommon0 libxkbfile-dev libxmu-dev libxmu-headers libxmuu-dev libxpm-dev libxrandr-dev libxrender-dev libxres-dev libxss-dev
  libxt-dev libxtst-dev libxv-dev libxvmc-dev libxxf86dga-dev libxxf86vm-dev linux-libc-dev m4 manpages-dev mesa-common-dev mir-client-platform-mesa-dev opencl-c-headers opencl-clhpp-headers
  opencl-headers php-cli php-common php-xml php7.2-cli php7.2-common php7.2-json php7.2-opcache php7.2-readline php7.2-xml vulkan-utils x11proto-composite-dev x11proto-core-dev x11proto-damage-dev
  x11proto-dev x11proto-dri2-dev x11proto-fixes-dev x11proto-fonts-dev x11proto-gl-dev x11proto-input-dev x11proto-randr-dev x11proto-record-dev x11proto-render-dev x11proto-resource-dev
  x11proto-scrnsaver-dev x11proto-xext-dev x11proto-xf86bigfont-dev x11proto-xf86dga-dev x11proto-xf86vidmode-dev x11proto-xinerama-dev xorg-dev xorg-sgml-doctools xserver-xorg-dev xtrans-dev zlib1g-dev
Suggested packages:
  autoconf-archive gnu-standards autoconf-doc libtool cmake-doc ninja-build g++-multilib g++-7-multilib gcc-7-doc libstdc++6-7-dbg git-daemon-run | git-daemon-sysvinit git-doc git-el git-email git-gui
  gitk gitweb git-cvs git-mediawiki git-svn glibc-doc libcurl4-doc libidn11-dev libkrb5-dev libldap2-dev librtmp-dev libssh2-1-dev gmp-doc libgmp10-doc libmpfr-dev libice-doc libsm-doc libssl-doc
  libstdc++-7-doc libxaw-doc libxcb-doc libxext-doc libxt-doc m4-doc opencl-clhpp-headers-doc php-pear
The following packages will be REMOVED:
  ubuntu-desktop xorg xserver-xorg-hwe-18.04
The following NEW packages will be installed:
  apt-file autoconf automake autotools-dev build-essential checkbox-provider-phoronix cmake cmake-data g++ g++-7 git git-man libc-dev-bin libc6-dev libcapnp-0.6.1 libcurl4-openssl-dev libdmx-dev libdmx1
  libdrm-dev liberror-perl libexpat1-dev libfontconfig1-dev libfontenc-dev libfreetype6-dev libfs-dev libfs6 libgmp-dev libgmp3-dev libgmpxx4ldbl libice-dev libjsoncpp1 libmirclient-dev libmirclient9
  libmircommon-dev libmircommon7 libmircookie-dev libmircookie2 libmircore-dev libmircore1 libmirprotobuf3 libpciaccess-dev libpixman-1-dev libpng-dev libpng-tools libprotobuf-dev libprotobuf-lite10
  libpthread-stubs0-dev libregexp-assemble-perl librhash0 libsigsegv2 libsm-dev libssl-dev libstdc++-7-dev libuv1 libvulkan-dev libvulkan1 libx11-dev libx11-doc libxau-dev libxaw7-dev libxcb1-dev
  libxcomposite-dev libxcursor-dev libxdamage-dev libxdmcp-dev libxext-dev libxfixes-dev libxfont-dev libxft-dev libxi-dev libxinerama-dev libxkbcommon-dev libxkbfile-dev libxmu-dev libxmu-headers
  libxmuu-dev libxpm-dev libxrandr-dev libxrender-dev libxres-dev libxss-dev libxt-dev libxtst-dev libxv-dev libxvmc-dev libxxf86dga-dev libxxf86vm-dev linux-libc-dev m4 manpages-dev mesa-common-dev
  mir-client-platform-mesa-dev opencl-c-headers opencl-clhpp-headers opencl-headers php-cli php-common php-xml php7.2-cli php7.2-common php7.2-json php7.2-opcache php7.2-readline php7.2-xml
  plainbox-provider-sru vulkan-utils x11proto-composite-dev x11proto-core-dev x11proto-damage-dev x11proto-dev x11proto-dri2-dev x11proto-fixes-dev x11proto-fonts-dev x11proto-gl-dev x11proto-input-dev
  x11proto-randr-dev x11proto-record-dev x11proto-render-dev x11proto-resource-dev x11proto-scrnsaver-dev x11proto-xext-dev x11proto-xf86bigfont-dev x11proto-xf86dga-dev x11proto-xf86vidmode-dev
  x11proto-xinerama-dev xorg-dev xorg-sgml-doctools xserver-xorg-dev xtrans-dev zlib1g-dev
The following packages will be upgraded:
  libdrm-amdgpu1 libdrm-common libdrm-intel1 libdrm-nouveau2 libdrm-radeon1 libdrm2 libxkbcommon-x11-0 libxkbcommon0
8 upgraded, 130 newly installed, 3 to remove and 255 not upgraded.
Need to get 45.1 MB of archives.
After this operation, 230 MB of additional disk space will be used.
Do you want to continue? [Y/n]
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-> ubuntu-desktop xorg xserver-xorg-hwe-18.04 packages are marked as being removed. I'm not sure if this is normal, and xorg-related tests in OEM providers fail because of this.

After investigating using apt-rdepends, it seems that the problem comes from checkbox-provider-phoronix (see attached log which is the output of `apt-rdepends -p -s Depends,PreDepends,Conflicts plainbox-provider-sru` for more info).