D12490: concatPaths: process empty path1 correctly

[Алексей Шилин]

aleksejshilin added reviewers: anthonyfieroni, dfaure.

REPOSITORY
  R241 KIO

REVISION DETAIL
  https://phabricator.kde.org/D12490

To: aleksejshilin, #frameworks, anthonyfieroni, dfaure
Cc: michaelh, bruns