[Merge] lp:~juliank/ubuntu-release-upgrader/double-check-source-release into lp:ubuntu-release-upgrader

[Julian Andres Klode]

The proposal to merge lp:~juliank/ubuntu-release-upgrader/double-check-source-release into lp:ubuntu-release-upgrader has been updated.

Description changed to:

Check that a sources.list entry for the "from" distribution exists
before attempting to upgrade (LP: #1725359)



For more details, see:
https://code.launchpad.net/~juliank/ubuntu-release-upgrader/double-check-source-release/+merge/337258
-- 
Your team Ubuntu Core Development Team is requested to review the proposed merge of lp:~juliank/ubuntu-release-upgrader/double-check-source-release into lp:ubuntu-release-upgrader.