Upgrading to bionic fails

[Jarno Suni]

It did not give reason. I have HWE Stacks installed in Xenial.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: ubuntu-release-upgrader-core 1:16.04.26
ProcVersionSignature: Ubuntu 4.15.0-47.50~16.04.1-generic 4.15.18
Uname: Linux 4.15.0-47-generic x86_64
NonfreeKernelModules: nvidia_uvm nvidia
ApportVersion: 2.20.1-0ubuntu2.18
Architecture: amd64
CrashDB: ubuntu
CurrentDesktop: XFCE
Date: Sat Apr 20 13:24:21 2019
EcryptfsInUse: Yes
InstallationDate: Installed on 2015-11-21 (1245 days ago)
InstallationMedia: Xubuntu 15.10 "Wily Werewolf" - Release amd64 (20151021)
PackageArchitecture: all
SourcePackage: ubuntu-release-upgrader
UpgradeStatus: Upgraded to xenial on 2019-04-20 (0 days ago)
VarLogDistupgradeTermlog:

[Brian Murray (brian-murray)]

I was unable to recreate this bug after restoring the apt-clone file provided in the attachments. The only difference, according to apt-clone, between the system I test with and your system was the fact that my system had apt-clone and dpkg-repack installed while your system had dropbox and google-chrome-stable. Perhaps it is one of those two packages causing the failure to calculate the upgrade. Please try removing them and report back regarding your results. Thanks in advance.

[Jarno Suni (jarnos)]

I removed dropbox and google-chrome-stable, but it did not help.
/var/log/dist-upgrade/apt.log contains several Broken things, here is some extraction:

Starting pkgProblemResolver with broken count: 46
Starting 2 pkgProblemResolver with broken count: 46
Investigating (0) libegl1 [ amd64 ] < none -> 1.0.0-2ubuntu2 | 1.0.0-2ubuntu2.2 > ( libs )
Broken libegl1:amd64 Depends on libegl-mesa0 [ amd64 ] < none -> 18.0.0~rc5-1ubuntu1 | 18.2.8-0ubuntu0~18.04.2 > ( libs )
  Considering libegl-mesa0:amd64 1 as a solution to libegl1:amd64 56
  MarkKeep libegl1 [ amd64 ] < none -> 1.0.0-2ubuntu2 | 1.0.0-2ubuntu2.2 > ( libs ) FU=0
  Holding Back libegl1:amd64 rather than change libegl-mesa0:amd64

[Jarno Suni (jarnos)]

The whole log file is about 300 kB. Should it be attached?

[Launchpad Janitor (janitor)]

[Expired for ubuntu-release-upgrader (Ubuntu) because there has been no activity for 60 days.]