DistUpgradeFetcherKDE crashes on method _warning

[Harald Sitter]

# Impact
DistUpgradeFetcherKDE.py calls self._warning() but in fact _warning is not an instance method of the fetcher but rather a global helper. This causes early unhandled exceptions to entirely defunc the fetcher rendering upgrades with the KDE UI impossible. NB: this only happens iff there was a problem getting the release notes to begin with.

This was fixed in https://launchpad.net/ubuntu/+source/ubuntu-release-upgrader/1:15.10.4 and needs to be SRU'd into vivid as it also suffers from the problem.

# Test Case
- setup a apt-cacher-ng as proxy
> $ cat /etc/apt/apt.conf.d/apt-cacher
> Acquire::http { Proxy "http://localhost:3142"; };
- run `kdesudo -- do-release-upgrade -m desktop -f DistUpgradeViewKDE`
- should come up with installer

# Regression Potential
Can't break anymore than getting another undefined method exception as we do now.

# Other Info
In testing I didn't actually get the fetcher UI itself to display, so I expect there is more wrong. It would however be a good start to not have it crash.

[Chris J Arges (arges)]

Hello Harald, or anyone else affected,

Accepted ubuntu-release-upgrader into vivid-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/ubuntu-release-upgrader/1:15.04.14.3 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, and change the tag from verification-needed to verification-done. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed. In either case, details of your testing will help us make a better decision.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance!

[Harald Sitter (apachelogger)]

Verified fixed with proposed. Upgrader doesn't crash but correctly displays an error.

[Launchpad Janitor (janitor)]

This bug was fixed in the package ubuntu-release-upgrader - 1:15.04.14.3

---------------
ubuntu-release-upgrader (1:15.04.14.3) vivid; urgency=medium

  * KDE: Access _warning helper correctly to prevent a crash in the fetcher
    LP: #1507886

 -- Harald Sitter <email address hidden> Tue, 20 Oct 2015 08:28:14 +0200

[Brian Murray (brian-murray)]

The verification of the Stable Release Update for ubuntu-release-upgrader has completed successfully and the package has now been released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.