Use a well-known 'third-party/' prefix for dependency paths of non-KDE modules.

See also issue: #26
Depends on Phabricator diff D20279: https://phabricator.kde.org/D20279
2 jobs for <span class="ref-name">remove-non-kde-modules-hack</span> in 1 minute and 11 seconds
Status Job ID Name Coverage
  Test
passed #3704
smoke-test

00:01:11

passed #3703
unit-test

00:00:36